Phylogeographic structure and historical dispersal of Schistosoma japonicum across East and Southeast Asia

Phylogeographic structure and historical dispersal of Schistosoma japonicum across East and Southeast Asia | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Phylogeographic structure and historical dispersal of Schistosoma japonicum across East and Southeast Asia Martin Nelwan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9212654/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 11 You are reading this latest preprint version Abstract The evolutionary relationships and geographic differentiation of Schistosoma japonicum populations across East and Southeast Asia remain incompletely resolved. This study investigated phylogenetic structure and regional dispersal patterns using mitochondrial genomes and ND1, ND4, and COX3 gene sequences from 84 isolates. Phylogenetic reconstruction revealed clear divergence between S. japonicum and S. sinensium , supporting their distinct evolutionary positions within the Asian schistosome lineage. Comparative analyses further identified pronounced genetic differentiation between Chinese populations and isolates form Taiwan. ND1 sequence comparations demonstrated extremely high genetic identity exceeding 99% among strains from China, Japan, Indonesia, and the Philippines. These results indicate strong genetic continuity among geographically distant populations despite wide regional separation. Phylogeographic patterns support a mainland Chinese origin followed by historical dispersal toward Japan and Southeast Asian archipelagos. These findings provide new insights into the evolutionary history and regional dissemination pathways of S. japonicum across East and Southeast Asia. Biological sciences/Ecology Earth and environmental sciences/Ecology Biological sciences/Evolution Biological sciences/Genetics Biological sciences/Microbiology Oncomelania Schistosoma sinensium Schistosoma japonicum Schistosomiasis japonica Figures Figure 1 Figure 2 Figure 3 Figure 4 Figure 5 1. Introduction Schistosoma japonicum causes schistosomiasis japonica in both humans and animals [ 1 ]. In definitive hosts, it resides in the portal and mesenteric veins [ 2 ], causing intestinal schistosomiasis in humans [ 3 – 5 ]. Schistosomiasis japonica is a waterborne disease of ancient origin, with evidence suggesting its existence for over 2,100 years. Symptoms resembling ascites and splenomegaly have been traced back to as far as 2,697 B.C., clinical symptoms similar to those of Katayama syndrome have been known since 400 B.C [ 6 ]. The disease is found in East Asia and Southeast Asia [ 7 ]. In East Asia, S. japonicum occurs in China and Taiwan [ 8 – 12 ], though it is no longer relevant in Japan. In Southeast Asia, the parasite is found in Indonesia and the Philippines [ 12 – 14 ]. In terms of recent statistics, S. japonicum infected 37,600 people in China in 2017 [ 15 ], 216 people in Indonesia in 2022 [ 16 ], and 2.7 million people in the Philippines [ 17 ]. Approximately 70 million people are at risk of S. japonicum infection in Asia [ 18 – 20 ]. S. japonicum split from S. sinensium [ 21 ]. Phylogenetic analyses have presented conflicting findings regarding its origin. Some studies suggest S. japonicum is derived from Sichuan and Yunnan Provinces, China, and then radiated eastward along the Yangtze River, establishing itself in central and eastern China [ 22 ]. In contrast, a phylogenetic reconstruction by Yin et al. , which used the S. japonicum mitochondrial DNA (mtDNA) genome, revealed a different pattern: the species originated the lake regions and the eastern Yangtze River before radiating to western China, Japan, and Southeast Asia [ 23 ].. The life cycle of S. japonicum requires both snails and vertebrate hosts. The intermediate host is the amphibious snail Oncomelania spp. [ 11 ], while definitive hosts include diverse mammals [ 14 ]. Although schistosomes are known to infect birds [ 24 – 26 ], the role of avian species in S. japonicum transmission remains uncertain. However, evidence shows that zoonotic species can infect wild birds [ 27 ], suggesting that birds may contribute to transmission of S. japonicum parasites. Dunbar et al. (2024) emphasized that mobile avian hosts may facilitate local spread through coprophagy and fecal contamination [ 28 ], while Diaz et al. (2023) suggested that the adaptive nature of schistosomes may allow future host shifts to new host [ 29 ], including birds as dfinitive host of S. japonicum . Further research is needed to clarify their role. A single S. japonicum female can release approximately 3,500 eggs per day [ 30 ]. In freshwater, eggs hatch into miracidia, which then seek the intermediate host [ 3 ], Oncomelania snails. Oncomelania can release approximately 15 to 160 cercariae per day. These cercariae then seek and infect definitive hosts [ 7 , 31 ]. The transmission and spread of schistosomiasis japonica lead to genetic diversity in the parasite. Various tools, such as population genetic analyses and sequencing technologies, can be used to predict these diversities. Molecular markers, such as the ND1, ND4, and COX3 genes, as well as those within the mitochondria, are available to assess S. japonicum genetic diversity. For example, Zhao et al. used the ND1 and the ND4 genes in a study that suggested the Taiwanese S. japonicum population was genetically distinct and completely diverged from the others [ 9 , 32 ]. Endemic populations of S. japonicum in China, Indonesia, and the Philippines show different levels of diversity, and the overall genetic diversity of the species is high [ 9 , 32 , 33 ]. Several bioinformatic tools can be used to align DNA sequences and reconstruct phylogenetic relationships, including ClustalW, NCBI BLAST and ETE. For example, NCBI BLAST compares nucleotide or protein sequences to sequence databases and calculates the statistical significance of matches [ 34 ]. The E value from BLAST, which is an expectation value, can be used to infer homology. An E value < 0.01 or E < 0.05 suggests a statiscally significant match. Although a low E value and a low P value can be roughly equivalent when the E value is very small, they are distinct statistical concepts [ 35 ]. BLAST can also be used to infer functional and evolutionary relationships and help identify members of a gene family [ 34 ]. The ETE toolkit can provide phylogenetic outputs from inference methods such as PhyML and RaxML. This study examines phylogeographic patterns of S. japonicum across East Asia and Southeast Asia, considering its evolutionary relationships with S. sinensium , using 84 mitochondrial sequences. 2. Materials and methods Sources for this research included academic platforms such as NCBI, PubMed, ScienceDirect, UC Berkeley, UNESCO, and WHO platforms. All content from the NCBI, UC Berkeley, UNESCO, and WHO platforms was open access, with rights for free reuse, though one ScienceDirect article was not. Nucleotide NCBI BLAST was performed to obtain E values and identity percentages, which were then used to construct slanted cladograms. This method allows reproducible data (nucleotide sequences) deposited in GenBank. A threshold of E ≤ 0.05 was used to identify significant matches, corresponding to default algorithm parameters (e.g., match/mismatch scores and filter of low complexity regions) [ 35 ]. In this research, sequences were included if they represented verified closely related within S. sinensim and S. japonicum or within S. japonicum itself for mitochondrial genes [ 21 ]. These include the ND1 partial coding regions, ND1 complete coding regions, ND4 complete coding regions, COX3 partial coding regions, or complete mitochondrial genome. The resulting cladograms illustrated close evolutionary relationships among organisms, with the highest percentage match within each group indicating the inferred relationship. These data was used to determine the phylogenetic relationships of S. japonicum from the Yangtze River Basin (Yunnan, Jiangxi, and Jiangsu) and to compare with isolates from other regions, including Japan, Indonesia, Taiwan, and the Philippines. In certain case, PhyML were used to support NCBI BLAST results. In this study, sequences were selected to reveal the evolutionary relationships of S. sinensium (Sichuan, China) with S. japonicum (China and Taiwan), using S. indicum (Bangladesh) as an outgroup. These sequences were also used to investigate the evolutionary relationships of S. japonicum from Jiangxi, China, by comparing them with isolates from other regions of China, Japan, Taiwan, the Philippines, and Indonesia. Sequences with less than 90% identity were identified as different species ( S. indicum, S. japonicum, S. malayensis, S. mekongi, S. ovuncatum , and S. sinensium ). All sequence data for S. sinensium and S. japonicum were sourced from the NCBI database. A tiered BLAST approach was used, where a standard megablast search was first performed, followed by a more sensitive BLASTn search if the results were nonsignificant [ 9 ]. Pairwise dot plots and the coding sequence (CDS) feature were employed to identify sequence differences. The analysis focused on determining the number of base and amino acid variations, which provides valuable insight into the genetic diversity S. japonicum strains. Note that formal analyses for base substitutions and amino acid replacements were not conducted. A total of 84 mitochondrial sequences of S. japonicum and S. sinensium were included in the present study. 2.1. Nucleotide BLAST for relationship between S. sinensium and S. japonicum For this nucleotide BLAST analysis, reference sequences were obtained from the GenBank database at the NCBI. Sequences of the ND1 gene (including partial and CDS) and other mitochondrial DNA were used to investigate the relationships between S. sinensium and S. japonicum populations within the Yangtze River Basin, China. The accession numbers for the sequences are provided in Table S1 . The relatioonships between S. sinensium and S. japonicum were analyzed using nucleotide BLAST. The resulting percentage identities, E values, and slanted cladograms were used to compare sequences from provincies within the Yangtze River Basin (Yunnan, Jiangxi, and Jiangsu) and Taiwan. These data were analyzed to identify the S. japonicum lineage most closely related to S. sinensium. The branches of the slanted cladogram illustrate the rlationships among S. japonicum poulations and their infection areas. S. indicum was used as an outgroup to root the phylogenetic tree and infer evoultonary relationships. A total of 84 mitochondrial sequences of S. japonicum and S. sinensium were ultimately selected from GenBank and used for subsequent phylogenetic analyses. 2.2. Relationships between the ND1 of S. japonicum For nucleotide BLAST analysis of S. japonicum , reference sequences were obtained from the GenBank database (NCBI). Specifically, the complete mitochondrial ND1 CDS was retrieved. The GenBank data were sourced from the study by Yin et al. (2015) [ 32 ], and the accession numbers are detailed in Table S2 . Nucleotide BLAST results were used to determine the phylogenetic relationships of S. japonicum in the study regions. These results provided percentage identity, E value, and a slanted cladogram to visualize relationships among the isolates. 2.3. Relationships between the ND4 gene of S. japonicum For nucleotide BLAST analysis, the complete mitochondrial ND4 CDS of S. japonicum was obtained as a reference from GenBank (NCBI). The sequence data were sourced from the study by Yin et al. (2015) [ 32 ] and included sequences from China, Japan, Indonesia, the Philippines, and Taiwan. The accession numbers for the sequences used in this analysis are listed in Table S3 . The percentage identity, E values, and a slanted cladogram derived from nucleotide BLAST were used to analyzed the phylogenetic relationships and infer the origin of S. japonicum populations in China, Japan, Indonesia, the Philippines, and Taiwan. 2.4. Relationships between the COX3 gene and mitochondria in S. japonicum For nucleotide BLAST analysis, reference sequences were accessed from the GenBank database at the NCBI. This dataset included both the partial COX3 CDS and complete mitochondrial genomes from various regions. Data were sourced from China, Indonesia, Japan, Taiwan and the Philippines. The accession numbers for all sequences used are detailed in Table S4 . . The phylogenetic relationships of S. japonicum populations from China, Japan, Indonesia, Taiwan, and the Philippines were analyzed using nucleotide BLAST. Percentage identities and E values were obtained, and the resulting data were used to construct a slanted cladogram that visualizes the relationships between parasites from these regions. ClustalW and RaxML were used to obtain cladogram to be compared to cladogram of NCBI BLAST. 2.5. Relationships among the complete mitochondrial genome of S. japonicum Reference sequences for the complete mitochondrial genome of S. japonicum were obtained from the GenBank database at NCBI for nucleotide BLAST analysis. These data were originally published by Yin et al. (2015) [ 23 ] and include sequences from China, Japan, Indonesia, the Philippines, and Taiwan. The accession numbers for the sequences used in this study are provided in Table 5. Nucleotide BLAST results from the complete mitochondrial genome were used to determine the percentage identity, E value, and phylogenetic relationships of S. japonicum populations across China, Japan, Indonesia, the Philippines, and Taiwan. The branches of the resulting cladogram illustrate the relationships among parasite populations in these regions. 3. Results 3.1 Sequence analysis of S. sinensium and S. japonicum Phylogenetic analyses were performed using 84 mitochondrial sequences of S. japonicum and S. sinensium across East and Southeast Asia. A BLASTn of the ND1 gene revealed that Sichuan S. sinensium shares 73.23% identity with Taiwan S. japonicum . Expanding on this, more sequences revealed that Taiwan S. japonicum shares 96.87% identity with S. japonicum fromYunnan, which represents the highest percentage found in mainland China. The analysis further detailed the close relationships between mainland China strains: Yunnan S. japonicum shares 99.87% identity with the Sichuan strain, which, in turn, shares 99.61% identity with the Jiangxi and Anhui Guichi strains and 99.35% identity with the Hunan Changde strain. In contrast, Sichuan S. sinensium displayed lower identity percentages with other strains: 72.29% with Anhui Guichi and Jiangxi S. japonicum , 72.04% with Anhui Tongling S. japonicum , and 71.79% with strains from Jiangsu, Sichuan, and Yunnan. The identity values for Hubei, Hunan Yueyang, and Hunan Changde S. japonicum were 71.54%, 71.46%, and 71.28%, respectively, while the identity with Bangladesh S. indicum was 75.00% (Table 1 , Fig. 1 , and Figure S1 ). In addition, Sichuan S. sinensium exhibited 106 base substitutions and 54 amino acid replacements compared to Jiangxi and Anhui Guichi S. japonicum , and 107 base substitutions and 54 amino acid replacements compared to Anhui Tongling S. japonicum. Table 1 Accession, E-value and percentage of Schistosoma sinensium and Schistosoma japonicum relationships for the ND1 gene Species Accession E-value S. sinensium AF465913.1 S. japonicum FJ852203.1 3e-53 72.29% S. japonicum KP793743.1 3e-53 72.29% S. japonicum FJ852232.1 4e-52 72.04% S. japonicum FJ852250.1 2e-50 71.79% S. japonicum FJ852220.1 2e-50 71.79% S. japonicum FJ852216.1 2e-50 71.79% S. japonicum FJ852248.1 2e-49 71.54% S. japonicum KP793758.1 4e-51 71.46% S. japonicum FJ852245.1 8e-48 71.28% S. japonicum KP793776.1 6e-62 73.23% S. indicum NC_047240 2e-16 75.00% S.: Schistosoma The cladogram (Fig. 1 ) illustrates three main branches. The first branch, positioned separately from the others, includes S. indicum from Bangladesh, S. sinensium from Sichuan, S. japonicum from Taiwan, and S. japonicum from Hunan Yueyang. A second branch comprises S. japonicum from Anhui Guichi, Jiangxi, Anhui Tongling, Jiangsu, Hubei, and Hunan Changde. The third branch is composed of S. japonicum from Yunnan and Sichuan. 3.2 Sequence analysis of the ND1 gene in S. japonicum Megablast sequencing results for the mitochondrial ND1 gene (complete CDS) revealed a 100% identity between Jiangxi S. japonicum and Hunan Changde S. japonicum . A 99.89% identity was observed with S. japonicum strains from Anhui Guichi, Anhui Tongling, Hunan Yueyang, Indonesia, the Philippines, and Yunnan. A comparison also showed that Jiangxi S. japonicum shares 99.78% identity with Indonesian and Sichuan S. japonicum , a 99.66% identity with Japanese S. japonicum , a 99.55% identity with Hunan Yueyang S. japonicum , a 99.44% identity with Hubei S. japonicum , a 99.33% identity with another Indonesian S. japonicum , and a 96.75% identity with Taiwan S. japonicum . All resulting E values were 0.0 (Table 2 and Fig. 2 ). Table 2 Accession, E value and percentage of Schistosoma japonicum relationships for the ND1 gene, complete CDS, mitochondrial Species Accession E-value S. japonicum KP793763.1 S. japonicum KP793756.1 0.0 100% S. japonicum KP793743.1 0.0 99.89% S. japonicum KP793747.1 0.0 99.89% S. japonicum KP793759.1 0.0 99.89% S. japonicum KP793779.1 0.0 99.89% S. japonicum KP793769.1 0.0 99.89% S. japonicum KP793783.1 0.0 99.89% S. japonicum KP793777.1 0.0 99.78% S. japonicum KP793765.1 0.0 99.78% S. japonicum KP793780.1 0.0 99.66% S. japonicum KP793758.1 0.0 99.55% S. japonicum KP793749.1 0.0 99.44% S. japonicum KP793778.1 0.0 99.33% S. japonicum KP793776.1 0.0 96.75% S. indicum NC_047240.1 4e-50 66.06% S.: Schistosoma The cladogram (Fig. 2 ) shows that Yunnan and Taiwan S. japonicum form a separate branch. Strains from Anhui Tongling and Sichuan are clustered together, as are S. japonicum from Japan, Hunan, and Hubei. A comparison between Japanese S. japonicum and Hunan Yueyang S. japonicum showed 99.66% identity, with different three base substitutions but no amino acid replacements. When compared with Hubei S. japonicum , it showed a 99.55% identity, with four base substituions and one amino acid replacement. In addition, Indonesian and Philippine S. japonicum each had one base substitution relative to Jiangxi S. japonicum . 3.3 Sequence analysis of the ND4 gene in S. japonicum The megablast analysis for the complete mitochondrial CDS, specifically the ND4 gene, revealed that Jiangxi S. japonicum shares 99.92% identity with S. japonicum from Sichuan and Yunnan. The identity with Anhui Guichi and Hunan Changde was 99.84%, and with Anhui Tongling S. japonicum was 99.76%. Jiangxi S. japonicum also showed 99.69% identity with Hunan Yueyang S. japonicum , all Indonesian strains, and the Philippine strain. Further comparisons yielded an identity of 99.61% with Japan S. japonicum ; 99.45% with Hunan Yueyang S. japonicum , 99.44% with Hubei S. japonicum , and 97.73% with Taiwan S. japonicum . All E values were 0.0 (Table 3 and Fig. 3 ). Table 3 Accession, E value and percentage of Schistosoma japonicum relationships for the ND4 gene, complete CDS, mitochondrial Species Accession E-value S. japonicum KP793805.1 S. japonicum KP793807.1 0.0 99.92% S. japonicum KP793811.1 0.0 99.92% S. japonicum KP793785.1 0.0 99.84% S. japonicum KP793798.1 0.0 99.84% S. japonicum KP793789.1 ).0 99.76% S. japonicum KP793801.1 0.0 99.69% S. japonicum KP793819.1 0.0 99.69% S. japonicum KP793820.1 0.0 99.69% S. japonicum KP793821.1 0.0 99.69% S. japonicum KP793825.1 0.0 99.69% S. japonicum KP793822.1 0.0 99.61% S. japonicum KP793800.1 0.0 99.45% S. japonicum KP793791.1 0.0 99.37% S. japonicum KP793818.1 0.0 97.37% S. indicum NC_047240.1 9e-42 66.05% S.: Schistosoma Based on the cladogram and sequence analysis (Fig. 3 ), Taiwanese S. japonicum forms a distinct, stand-alone branch. Japan S. japonicum is clustered with Hunan Yueyang and Hubei S. japonicum. Within this group, Japan S. japonicum shares 99.69% identity with the Hunan Yueyang strain, differing by four base substitutions and two amino acid replacements. It shares 99.61% identity with the Hubei strain, a difference that includes five base substitutions and two amino acid replacements. In addition, Hunan Changde and Hunan Yueyang form a separate, distinct branch. Anhui Tongling S. japonicum clusters with the Philippine and Indonesian strains, sharing 99.76% identity with both. Compared to all Indonesian S. japonicum , it has three base substitutions and two amino acid replacements, while it has three base substitutions and one amino acid replacement when compared to the Philippine strain. Finally, Jiangxi S. japonicum is grouped with the strains from Anhui Guichi, Sichuan, and Yunnan. 3.4 Sequence analysis of the COX3 gene and complete mitochondrial genome in S. japonicum Megablast results for the COX3 gene, partial mitochondrial CDS, and complete mitochondrial genome revealed that Jiangxi S. japonicum shared 100% identity with strains from Sichuan, Anhui, and Jiangsu. It showed 99.83% identity with strains from Indonesia, Japan, the Philippines, Taiwan, Hunan, and Hubei, but only 96.65% identity with the Yunnan strain. All analyses yielded an E value of 0.0 (Table 4 , Fig. 4 , and Figure S1 ). Table 4 Accession, E-value and percentage of Schistosoma japonicum relationships for the COX3 gene Species Accession E-value S. japonicum EU927628.1 S. japonicum EU927627.1 0.0 100% S. japonicum EU927612.1 0.0 100% S. japonicum EU927635.1 0.0 100% S. japonicum JQ781214.1 0.0 99.83% S. japonicum JQ781215.1 0.0 99.83% S. japonicum KU196357.1 0.0 99.83% S. japonicum KF279410.1 0.0 99.83% S. japonicum EU927625.1 0.0 99.83% S. japonicum EU927619.1 0.0 99.83% S. japonicum EU927638.1 0.0 99.65% S.: Schistosoma Analysis of the slanted cladogram revealed that the Jiangsu and Yunnan S. japonicum sequences clustered on distinct branch. The Anhui Guichi and Taiwan strainss were grouped together, sharing 99.83% identity. The Jiangxi S. japonicum strain clustered with the Japan, the Philippines, and Indonesia strains. A comparison showed that while the Jiangxi strain had one base pair substitution, it exhibited no corresponding amino acid replacement when compared to other three strains. 3.5 Sequence analysis of the complete mitochondrial genome of S. japonicum Megablast results for the complete mitochondrial genome revealed that Jiangxi S. japonicum had varying degrees of identity with other strains (Table 5 and Fig. 5 ). The highest identity was observed with Anhui Tongling( 99.87%), followed by Hunan Yueyang (99.86%), Anhui Guichi, Indonesia, and the Philippines (99.82%); and Yunnan (99.81%). Lower identities were found with Sichuan (99.75%), Hubei (99.69%), Japan (99.40%), Hunan Yueyang (99.32%) and Taiwan (98.02%). All the E values were 0.0. In the slanted cladogram, S. japonicum from Taiwan formed, a distinct, stand-alone branch. The Japan strain was in the same group as the Hunan Yueyang strain, differing by 40 base substitutions and six amino acid replacements. A separate group included strains from Indonesia and te Philippines, Hunan Yueyang and Anhui Guichi. The Indonesian strain shared 99.89% identity with the Anhui Guichi strain, with 16 base substitutions and three amino acid replacements. The Indonesian strain also showed 99.80% identity with the Hunan Yueyang strain. Finally, the Philippine strain shared 99.87% identity with the Anhui Guuichi strain and 99.29% identity with the Hunan Yueyang strain, with 18 base substitutions and three amino acid replacements when compared to the Anhui Guichi strain. Table 5. Accession, E-value and percentage of Schistosoma japonicum relationshipps for the mitochondrial comple genome Species Accession E-value S. japonicum KU196367.1 S. japonicum KU196313.1 0.0 99.87% S. japonicum KU196317.1 0.0 99.87% S. japonicum KU196347.1 0.0 99.86% S. japonicum KU196305.1 0.0 99.82% S. japonicum KU196307.1 0.0 99.82% S. japonicum KU196348.1 0.0 99.82% S. japonicum KU196379.1 0.0 99.82% S. japonicum KU196408.1 0.0 99.81% S. japonicum KU196389.1 0.0 99.75% S. japonicum KU196318.1 0.0 99.69% S. japonicum KU196328.1 0.0 99.69% S. japonicum KU196359.1 0.0 99.40% S. japonicum KU196338.1 0.0 99.32% S. japonicum KU196398.1 0.0 98.02% S. indicum NC_047240.1 5e-150 75.14% S.: Schistosoma 4. Discussion S. sinensium diverged from S. ovuncatum [ 21 ]. Both S. ovuncatum and S. sinensium occur across China, India, and Thailand, reflecting their broad distribution within Asian schistosome lineages [ 37 ]. Subsequently, S. japonicum diverged from S. sinensium , followed by divergence of S. mekongi and S. malayensis from S. japonicum [ 21 ]. S. japonicum represents one of five species within this lineage, alongside S. ovuncatum, S. sinensium, S. mekongi , and S. malayensis [ 21 , 38 ]. Unlike its intermediate host genus Oncomelania , believed to originate from eastern Indonesia, S. japonicum spread from Chinese lake regions to East and Southeast Asia [ 21 , 23 ]. Consistent phylogenetic evidence indicates that S. japonicum remains closely related to S. sinensium within the broader Asian schistosome evolutionary lineage [ 21 , 37 – 38 ]. Previous study suggested that S. japonicum populations form four primary clades located in mainland Chinese, Indonesia, the Philippines, and Taiwan [ 39 ]. Taiwanese S. japonicum genetically distinct from other regional populations and diverged approximately forty-five thousand years ago [ 32 , 39 ]. Later divergence events occurred more recently, with Philippine populations separating from Chinese lake regions approximately seven thousand five hundred years ago. Subsequently, Sichuan and Yunnan populations diverged roughly five thousand four hundred years ago from earlier mainland Chinese ancestral lineages [ 39 ]. Indonesia and Japanese S. japonicum populations diverged from Chinese populations approximately five thousand years ago, reflecting later regional dispersal events. Some researchers therefore proposed that Taiwanese and Southeast Asian populations could represent subspecies within the broader S. japonicum lineage [ 39 ]. Notably, Taiwanese S. japonicum exhibits zoophilic behavior but lacks zoonotic transmission potential, distinguishing it from other regional populations [ 40 ]. Sequence analyses conducted in this study indicate that S. japonicum diverged from S. sinensium in Taiwan, followed by additional divergences events in Anhui Guichi and Jiangxi populations. Taiwanese S. japonicum exhibits greater genetically similarity to Yunnan strains than to several other mainland Chinese populations examined here. The Taiwanese strain shares 96.87% sequence identity with Yunnan S. japonicum , suggesting potential historical evolutionary connections between these regions. Yunnan strains display extremely high identity, approximately 99.87%, with S. japonicum populations from Sichuan, Anhui Guichi, and Jiangxi lake regions. High identity values between Yunnan and lake-region strains suggest eastward parasite dispersal from southwestern China toward central and eastern regions. This pattern agrees with Young et al. (2015) [ 22 ], who reported eastward spread forming central and eastern Chinese population group [ 21 , 22 ]. S. sinensium shares approximately 72% identity with Anhui Guichi and Jiangxi S. japonicum populations examined in this study. Approximately 73% identity was also observed between S. sinensium and Taiwanese S. japonicum , supporting their deeper evolutionary divergence (Table 1 , Fig. 1 , and Figure S1 ). Previous research suggested that S. japonicum spread from Anhui Guichi and Jiangxi lake regions toward mainland China, Japan, Indonesia, and the Philippines [ 23 ]. Sequence comparisons indicate that Sichuan S. sinensium shows closer genetic affinity to Anhui Guichi and Jiangxi S. japonicum than to Anhui Tongling populations. Sichuan S. japonicum displays 54 amino acid replacements relative to Anhui Guichi, Anhui Tongling, and Jiangxi populations. These patterns suggest strong genetic relatedness among Sichuan, Anhui Guichi, and Jiangxi S. japonicum strains. Evidence further indicates that Anhui Guichi and Jiangxi populations subsequently dispersed toward Anhui Tongling, Hubei, Jiangsu, Hunan, Yunnan, and Sichuan. The present findings also suggest increased prevalence of S. japonicum specifically within Anhui Guichi and Jiagxi lake regions. Earlier research did not clearly identify this geographic concentration of parasite populations within mainland China [ 23 , 39 ]. Phylogenetic evidence further suggests that Taiwanese S. japonicum populations represent older lineages relative to mainland Chinese populations. These results also support earlier conclusions that divergence of S. japonicum from S. sinensium occurred relatively early in Asian schistosome evolution [ 12 , 37 ]. ND1 gene sequences reveal complete identity between Jiangxi and Hunan Changde S. japonicum populations examined in this study (Table 2 ). Other mainland Chinese, Japanese, Indonesian, and Philippine populations show slightly lower identities ranging from 99.55% to 99.89%. These findings indicate that Southeast Asian and Japanese populations retain extremely close genetic relationships with mainland Chinese S. japonicum . Hunan Changde and Jiangxi strains share approximately 97% identity with Taiwanese S. japonicum , representing the lowest similarity among Asian strains examined. The ND1 cladogram further shows that Taiwanese and Yunnan S. japonicum form a distinct phylogenetic branch (Fig. 2 ). Anhui Tongling and Sichuan populations cluster within the same group, indicating strong genetic similarity between these regional populations. Japanese S. japonicum clusters with Hunan Yueyang and Hubei strains within the same phylogentic group. Japanese and Hunan Yueyang sequences display no amino acid replacements, whereas comparisons with Hubei reveal a single replacement. These findings suggest that Japanese S. japonicum likely originated from populations related to Hunan Yueyang lineage. All Indonesian and Philippine S. japonicum strains cluster together within the same phylogenetic group based on the ND1 gene sequences (Table 2 and Fig. 2 ). Indonesian populations share extermely high identity values between 99.44% and 99.89% with Jiangxi strains from mainland China. These results indicate that Southeast Asian populations likely originated from either Hunan Changde or Jiangxi ancestrl lineages. Sequence alignments show only one base substitution and amino acid replacements relative to Hunan Changde or Jiangxi strains. Previous reports suggested that Philippine lineages diverged first from Chinese lake populations before iving rise to Indonesian and Japanese lineages [ 39 ]. ND4 gene analyses indicate relatively low genetic divergence among mainland Chinese S. japonicum populations examined in this study. Jiangxi populations share greater than 99% identity with most mainland Chinese, Japanese, Indonesian, and Philippine strains (Table 3 ). These findings contrast with previous reports suggesting higher genetic divergence among Chinese S. japonicum populations [ 32 , 39 ]. Taiwanese populations show approximately 98% identity with Jinagxi populations, confirming deeper divergence from mainland Chinese strains. ND4 cladogram analyses further indicate that Japanese S. japonicum populations likely derived from Hunan Yueyang populations in central China. Japanese strains display similar amino acid replacements to those observed in Hunan Yueyang and Hubei populations (Fig. 3 ). However, Japanese strains show fewer base substitutions relative to Hunan Yueyang than to Hubei strains. These results further support a potential Hunan Yueyang origin for Japanese S. japonicum populations. Anhui Tongling populations share approximately 99.76% identity with Southeast Asian strains from Indonesia and the Philippines. Philippines strains shows one amino acid replacement relative to Anhui Tongling, whereas Indonesia strains exhibit two replacements. These findings suggests that Southeast Asian populations likely originated from Anhui Tongling ancestral lineages in mainland China. Identity values further suggest that Philippine populations diverged first, followed by Indonesian and Japanese populations. Analyses of COX3 gene sequences and complete mitochondrial genomes further clarify phylogenetic relationships among regional populations. Taiwanese populations shares 99.83% identity with Anhui Guichi and Jiangxi strains (Table 4 , Fig. 4 , and Figure S1 ). These findings suggest that Taiwanese populations may have originated from mainland Chinese populations. Jiangxi, Japanese, Indonesian, and Philippine populations cluster within the same phylogenetic group in mitochondrial analyses. Extremely high identity values and minimal amino acid replacements indicate recent divergence among these regional populations. Complete mitochondrial genome analyses further support relationships observed in gene-specific phylogenetic reconstructions. Japanese populations cluster closely with Hunan Yueyang strains, supporting previous interpretations of their evolutionary origin (Fig. 5 ). Indonesian populations cluster with Hunan Yueyang, Anhui Guichi, and Philippine populations in the same phylogenetic group. Lower substitution numbers relative to Anhui Guichi strains suggest ancestral relationships linking Southeast Asian populations with Chinese lake-region lineages. Mitochondrial analyses overall indicate that Japanese populations likely originated from central Chinese provinces including Hunan and Hubei. Southeast Asian populations were compared with strains from Anhui Guichi, Anhui Tongling, Hunan Changde, and Jiangxi. Results demonstrate extremely close genetic relationships among Chinese, Japanese, and Southeast Asian populations. However, Taiwanese populations form a distinct lineage that diverged earlier from other regional populations. Genetic studies also reveal that several Indonesian ethnic groups possess ancestral connections with populations from China or Taiwan [ 41 ]. These migrations occurred approximately three to four thousand years ago and may have facilitated parasite dispersal [ 23 ]. Archaeological evidence from megalithic cultural traditions in Central Sulawesi further supports ancient migration patterns within this region [ 41 ]. These patterns suggest that S. japonicum in Lore Lindu National Park may have been introduced from southern China approximately four thousand years ago [ 23 ]. Analyses of mitochondrial genome sequences, including ND1, ND4, COX3, and complete mitochondrial genomes, indicate that Japanase S. japonicum likely originated from Hunan and Hubei provinces. Comparative analyses of Southeast Asia and Chinese isolates further demonstrate close genetic relationships, with the exception of the distinct Taiwanese lineage. These findings provide new insights into the phylogeographic structure and historical patterns of S. japonicum across East and Southeast Asia. Although this study analyzed 84 mitochondrial sequences using robust phylogenetic approaches, the absence of nuclear genetic markers may limit resolution of deeper evolutionary relationships. Overall, the results contribute to a better understanding of parasite evolution and regional transmission dynamics. 5. Conclusions Studies on Schistosoma species reveal several key genetic relationships and dispersal patterns. The Sichuan S. sinensium lineage was the first to diverge into what is the Taiwanese S. japonicum . The Taiwanese population itself is a mix of the original strain and lineage from mainland China. In mainland China, the Yunnan S. japonicum population diversified, giving rise to the Sichuan, Anhui Guichi, and Jiangxi strains, which subsequently spread through the Far East, including Japan, the Philippines, Indonesia, and Taiwan. Specifically the Japanese S. japonicum strain originated from the Anhui Guichi, Hunan Yueyang, and Jiangxi. Similarly, the Southeast Asian S. japonicum strains are descendants of Chinese populations from Anhui Tongling, Anhui Guichi, Hunan Changde, and Jiangxi. Overall, the genetic evidence confirms a close relations between S. japonicum strains found in Japan and Southeast Asia and those in China. Declarations Acknowledgments : During the preparation of this work the author used ChatGPT for improving clarity, readability, and textual overlap with previously published works. After using these services, the author reviewed and edited the content as needed and take full responsibility for the content of the published article. 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Supplementary Files TableS1Srep.docx TableS2Srep.docx TableS3Srep.docx TableS4Srep.docx TableS5Srep.docx FigureS1Srep.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 23 Apr, 2026 Reviews received at journal 23 Apr, 2026 Reviews received at journal 15 Apr, 2026 Reviewers agreed at journal 09 Apr, 2026 Reviewers agreed at journal 02 Apr, 2026 Reviewers agreed at journal 01 Apr, 2026 Reviewers invited by journal 31 Mar, 2026 Editor invited by journal 31 Mar, 2026 Editor assigned by journal 25 Mar, 2026 Submission checks completed at journal 25 Mar, 2026 First submitted to journal 24 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9212654","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":615523264,"identity":"d0716a30-6c38-437a-bc4c-657b744c252e","order_by":0,"name":"Martin Nelwan","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA1UlEQVRIiWNgGAWjYDACdiB+AMT87A1A0sCCCC3MQJwAxJI9B0BaJEjQYnADRDIQoUW3mffgg8Q2uzyGm8+vbvhRIMHA396dgFeL2WG+ZIPEtuRixtk5ZTd7gA6TOHN2AwEtPGYSiduYE5ulc9Ju8AC1GEjkEtRi/iNxW31im+SZtJt/iNRixpC47XBijwT7sdvE2mIskfjveOIMnhy22zIGEjyE/XK8x/DDhzPVifuPH392880fGzn+9l78WpAAjwGYJFY5CLA/IEX1KBgFo2AUjCAAAHNyR+ZKFZgzAAAAAElFTkSuQmCC","orcid":"","institution":"Nelwan Institution for Human Resource Development","correspondingAuthor":true,"prefix":"","firstName":"Martin","middleName":"","lastName":"Nelwan","suffix":""}],"badges":[],"createdAt":"2026-03-24 13:38:43","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9212654/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9212654/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105904917,"identity":"d14461f0-f049-4488-a788-0f96ecd25335","added_by":"auto","created_at":"2026-04-01 10:11:04","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":271708,"visible":true,"origin":"","legend":"\u003cp\u003eNodes 21 (0 selected) and view port at (0,0) of 948x336. Cladogram illustrating phylogenetic relationships between \u003cem\u003eS. japonicum \u003c/em\u003eand \u003cem\u003eS. sinensium\u003c/em\u003eusing ND1 gene and the complete mitochondrial genome data( NCBI). Note the distinct branching of \u003cem\u003eS. indicum \u003c/em\u003eand the Taiwan (CTW%) lineage. The cladogram shows genetic divergence within \u003cem\u003eS. japonicum\u003c/em\u003e, with the Taiwan (73.23%), Jiangxi (72.29%), and Anhui Guichi (72.29%) isolates forming distinct clades. The yellow highlighting part in the figure body is Query Sequence and others are Subject Sequence.\u003c/p\u003e","description":"","filename":"floatimage1.png","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/5dd6d83c7ce79013ef9c42a8.png"},{"id":105905338,"identity":"62dd7fc0-aed5-4cb3-a084-dc2960fd92eb","added_by":"auto","created_at":"2026-04-01 10:11:52","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":379304,"visible":true,"origin":"","legend":"\u003cp\u003eNodes 31 (0 selected) and view port at (0,0) of 948x336. Tree view of \u003cem\u003eSchistosoma japonicum \u003c/em\u003erelationships for the ND1 gene, complete CDS; mitochondrial (taken from NCBI). For example, Yunnan \u003cem\u003eSchistosoma japonicum\u003c/em\u003e (YNEY2) forms a stand-alone branch. The yellow highlighting part in the figure body is Query Sequence and others are Subject Sequence.\u003c/p\u003e","description":"","filename":"floatimage2.png","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/ea01e4bff626f33af32b5d80.png"},{"id":105905454,"identity":"b4a4a004-059e-4be6-a511-467b2c19c386","added_by":"auto","created_at":"2026-04-01 10:12:12","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":377194,"visible":true,"origin":"","legend":"\u003cp\u003eNodes 31 (0 selected) and view port at (0,0) of 948x336. Tree-view of \u003cem\u003eSchistosoma japonicum \u003c/em\u003erelationships for the ND4 gene, complete CDS, and mitochondria. For example, Japan (JP1), Hunan Yueyang (HNYY2) and Hubei (HBSH1) are within the same group. The yellow highlighting part in the figure body is Query Sequence and others are Subject Sequence\u003c/p\u003e","description":"","filename":"floatimage3.png","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/48d23eda5826727cdd87154a.png"},{"id":105873486,"identity":"dec5110c-ad09-4b5b-b70d-99e9fbbe9442","added_by":"auto","created_at":"2026-04-01 05:17:40","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":269119,"visible":true,"origin":"","legend":"\u003cp\u003eNodes 21 (0 selected) and view port at (0,0) of 948x336.\u003cstrong\u003e \u003c/strong\u003eTree view of \u003cem\u003eSchistosoma japonicum \u003c/em\u003erelationships for the COX3gene mitochondrion, complete genome. For example, Sichuan \u003cem\u003eSchistosoma japonicum\u003c/em\u003e (SJSXM9) and Taiwan Changhua are within the same group. The yellow highlighting part in the figure body is Query Sequence and others are Subject Sequence.\u003c/p\u003e","description":"","filename":"floatimage4.png","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/fec1657143dc38ff4d1a18c1.png"},{"id":106723810,"identity":"782f6359-5822-424a-8d6e-450b7cb1e28c","added_by":"auto","created_at":"2026-04-12 18:15:33","extension":"png","order_by":5,"title":"Figure 5","display":"","copyAsset":false,"role":"figure","size":426227,"visible":true,"origin":"","legend":"\u003cp\u003eNodes (0 selected) and view at (0,0) of 948x336.\u003cem\u003e\u003cstrong\u003e. \u003c/strong\u003e\u003c/em\u003eTree view of\u003cem\u003e \u003c/em\u003ethe complete mitochondrial genome of \u003cem\u003eSchistosoma japonicum\u003c/em\u003e. For example, Taiwan TW0001 (KU196398.1) forms a stand-alone branch, and JP0002 (KU196359.1) and HNYY01 (KU196338.1) are within the same group. HNCD01 (KU196328.1), HBSS01 (KU196318.1), YNEY01 (KU196408.1), SCXC01 (KU196389.1), HNYY10 (KU196347.1), IN0001 (KU196348.1), AHGC09 (KU196307.1), AHGC07 (KU196305.1), PH0001 (KU196379.1), JXDC09 (KU196367.1), AHTL10 (KU196317.1), and AHTL06 (KU196313.1). The yellow highlighting part in the figure body is Query Sequence and others are Subject Sequence.\u003c/p\u003e","description":"","filename":"floatimage6.png","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/7a7e95d153b76b61bb254828.png"},{"id":106959637,"identity":"485e636e-7277-4aa2-bc18-315097febdb2","added_by":"auto","created_at":"2026-04-15 09:12:40","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2918006,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/4765e389-769a-4839-b63e-f407337df788.pdf"},{"id":105873480,"identity":"25754098-940f-4210-a20a-e63eb0533081","added_by":"auto","created_at":"2026-04-01 05:17:40","extension":"docx","order_by":0,"title":"","display":"","copyAsset":false,"role":"supplement","size":15160,"visible":true,"origin":"","legend":"","description":"","filename":"TableS1Srep.docx","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/617034c7489cf059254b6d99.docx"},{"id":105873483,"identity":"161826f5-f5ee-47f1-b83b-3e91a5389e7c","added_by":"auto","created_at":"2026-04-01 05:17:40","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":15414,"visible":true,"origin":"","legend":"","description":"","filename":"TableS2Srep.docx","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/6ad149392e8eada119479b5a.docx"},{"id":105873484,"identity":"9b486cc9-6001-40fe-9344-9b2855d44da3","added_by":"auto","created_at":"2026-04-01 05:17:40","extension":"docx","order_by":2,"title":"","display":"","copyAsset":false,"role":"supplement","size":15478,"visible":true,"origin":"","legend":"","description":"","filename":"TableS3Srep.docx","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/d15cc2198e60843ab0715e4b.docx"},{"id":105904687,"identity":"7d6b45c5-7743-4fc1-84dc-3d9d0762d8ec","added_by":"auto","created_at":"2026-04-01 10:10:15","extension":"docx","order_by":3,"title":"","display":"","copyAsset":false,"role":"supplement","size":14748,"visible":true,"origin":"","legend":"","description":"","filename":"TableS4Srep.docx","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/7f6d86a745f470e06f49901b.docx"},{"id":105873488,"identity":"6c391051-be7c-4fa3-b3da-c3a27132d962","added_by":"auto","created_at":"2026-04-01 05:17:40","extension":"docx","order_by":4,"title":"","display":"","copyAsset":false,"role":"supplement","size":15486,"visible":true,"origin":"","legend":"","description":"","filename":"TableS5Srep.docx","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/0004fedfdfb76d772c907e51.docx"},{"id":105873490,"identity":"6fa886be-9dc8-41fe-b80c-edc3796d8792","added_by":"auto","created_at":"2026-04-01 05:17:40","extension":"docx","order_by":5,"title":"","display":"","copyAsset":false,"role":"supplement","size":645127,"visible":true,"origin":"","legend":"","description":"","filename":"FigureS1Srep.docx","url":"https://assets-eu.researchsquare.com/files/rs-9212654/v1/8be39b11715d44267621477f.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Phylogeographic structure and historical dispersal of Schistosoma japonicum across East and Southeast Asia","fulltext":[{"header":"1. Introduction","content":"\u003cp\u003e \u003cem\u003eSchistosoma japonicum\u003c/em\u003e causes schistosomiasis japonica in both humans and animals [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. In definitive hosts, it resides in the portal and mesenteric veins [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e], causing intestinal schistosomiasis in humans [\u003cspan additionalcitationids=\"CR4\" citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Schistosomiasis japonica is a waterborne disease of ancient origin, with evidence suggesting its existence for over 2,100 years. Symptoms resembling ascites and splenomegaly have been traced back to as far as 2,697 B.C., clinical symptoms similar to those of Katayama syndrome have been known since 400 B.C [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. The disease is found in East Asia and Southeast Asia [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. In East Asia, \u003cem\u003eS. japonicum\u003c/em\u003e occurs in China and Taiwan [\u003cspan additionalcitationids=\"CR9 CR10 CR11\" citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e], though it is no longer relevant in Japan. In Southeast Asia, the parasite is found in Indonesia and the Philippines [\u003cspan additionalcitationids=\"CR13\" citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. In terms of recent statistics, \u003cem\u003eS. japonicum\u003c/em\u003e infected 37,600 people in China in 2017 [\u003cspan citationid=\"CR15\" class=\"CitationRef\"\u003e15\u003c/span\u003e], 216 people in Indonesia in 2022 [\u003cspan citationid=\"CR16\" class=\"CitationRef\"\u003e16\u003c/span\u003e], and 2.7\u0026nbsp;million people in the Philippines [\u003cspan citationid=\"CR17\" class=\"CitationRef\"\u003e17\u003c/span\u003e]. Approximately 70\u0026nbsp;million people are at risk of \u003cem\u003eS. japonicum\u003c/em\u003e infection in Asia [\u003cspan additionalcitationids=\"CR19\" citationid=\"CR18\" class=\"CitationRef\"\u003e18\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR20\" class=\"CitationRef\"\u003e20\u003c/span\u003e].\u003c/p\u003e \u003cp\u003e \u003cem\u003eS. japonicum\u003c/em\u003e split from \u003cem\u003eS.\u003c/em\u003e sinensium [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Phylogenetic analyses have presented conflicting findings regarding its origin. Some studies suggest \u003cem\u003eS. japonicum\u003c/em\u003e is derived from Sichuan and Yunnan Provinces, China, and then radiated eastward along the Yangtze River, establishing itself in central and eastern China [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. In contrast, a phylogenetic reconstruction by Yin \u003cem\u003eet al.\u003c/em\u003e, which used the \u003cem\u003eS. japonicum\u003c/em\u003e mitochondrial DNA (mtDNA) genome, revealed a different pattern: the species originated the lake regions and the eastern Yangtze River before radiating to western China, Japan, and Southeast Asia [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]..\u003c/p\u003e \u003cp\u003eThe life cycle of \u003cem\u003eS. japonicum\u003c/em\u003e requires both snails and vertebrate hosts. The intermediate host is the amphibious snail \u003cem\u003eOncomelania\u003c/em\u003e spp. [\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], while definitive hosts include diverse mammals [\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e]. Although schistosomes are known to infect birds [\u003cspan additionalcitationids=\"CR25\" citationid=\"CR24\" class=\"CitationRef\"\u003e24\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR26\" class=\"CitationRef\"\u003e26\u003c/span\u003e], the role of avian species in \u003cem\u003eS. japonicum\u003c/em\u003e transmission remains uncertain. However, evidence shows that zoonotic species can infect wild birds [\u003cspan citationid=\"CR27\" class=\"CitationRef\"\u003e27\u003c/span\u003e], suggesting that birds may contribute to transmission of \u003cem\u003eS. japonicum\u003c/em\u003e parasites. Dunbar et al. (2024) emphasized that mobile avian hosts may facilitate local spread through coprophagy and fecal contamination [\u003cspan citationid=\"CR28\" class=\"CitationRef\"\u003e28\u003c/span\u003e], while Diaz et al. (2023) suggested that the adaptive nature of schistosomes may allow future host shifts to new host [\u003cspan citationid=\"CR29\" class=\"CitationRef\"\u003e29\u003c/span\u003e], including birds as dfinitive host of \u003cem\u003eS. japonicum\u003c/em\u003e. Further research is needed to clarify their role.\u003c/p\u003e \u003cp\u003eA single \u003cem\u003eS. japonicum\u003c/em\u003e female can release approximately 3,500 eggs per day [\u003cspan citationid=\"CR30\" class=\"CitationRef\"\u003e30\u003c/span\u003e]. In freshwater, eggs hatch into miracidia, which then seek the intermediate host [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e], \u003cem\u003eOncomelania\u003c/em\u003e snails. \u003cem\u003eOncomelania\u003c/em\u003e can release approximately 15 to 160 cercariae per day. These cercariae then seek and infect definitive hosts [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e, \u003cspan citationid=\"CR31\" class=\"CitationRef\"\u003e31\u003c/span\u003e]. The transmission and spread of schistosomiasis japonica lead to genetic diversity in the parasite. Various tools, such as population genetic analyses and sequencing technologies, can be used to predict these diversities.\u003c/p\u003e \u003cp\u003eMolecular markers, such as the ND1, ND4, and COX3 genes, as well as those within the mitochondria, are available to assess \u003cem\u003eS. japonicum\u003c/em\u003e genetic diversity. For example, Zhao \u003cem\u003eet al.\u003c/em\u003e used the ND1 and the ND4 genes in a study that suggested the Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e population was genetically distinct and completely diverged from the others [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e]. Endemic populations of \u003cem\u003eS. japonicum\u003c/em\u003e in China, Indonesia, and the Philippines show different levels of diversity, and the overall genetic diversity of the species is high [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR33\" class=\"CitationRef\"\u003e33\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSeveral bioinformatic tools can be used to align DNA sequences and reconstruct phylogenetic relationships, including ClustalW, NCBI BLAST and ETE. For example, NCBI BLAST compares nucleotide or protein sequences to sequence databases and calculates the statistical significance of matches [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. The E value from BLAST, which is an expectation value, can be used to infer homology. An E value\u0026thinsp;\u0026lt;\u0026thinsp;0.01 or E\u0026thinsp;\u0026lt;\u0026thinsp;0.05 suggests a statiscally significant match. Although a low E value and a low P value can be roughly equivalent when the E value is very small, they are distinct statistical concepts [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. BLAST can also be used to infer functional and evolutionary relationships and help identify members of a gene family [\u003cspan citationid=\"CR34\" class=\"CitationRef\"\u003e34\u003c/span\u003e]. The ETE toolkit can provide phylogenetic outputs from inference methods such as PhyML and RaxML.\u003c/p\u003e \u003cp\u003eThis study examines phylogeographic patterns of \u003cem\u003eS. japonicum\u003c/em\u003e across East Asia and Southeast Asia, considering its evolutionary relationships with \u003cem\u003eS. sinensium\u003c/em\u003e, using 84 mitochondrial sequences.\u003c/p\u003e"},{"header":"2. Materials and methods","content":"\u003cp\u003eSources for this research included academic platforms such as NCBI, PubMed, ScienceDirect, UC Berkeley, UNESCO, and WHO platforms. All content from the NCBI, UC Berkeley, UNESCO, and WHO platforms was open access, with rights for free reuse, though one ScienceDirect article was not.\u003c/p\u003e \u003cp\u003eNucleotide NCBI BLAST was performed to obtain E values and identity percentages, which were then used to construct slanted cladograms. This method allows reproducible data (nucleotide sequences) deposited in GenBank. A threshold of E\u0026thinsp;\u0026le;\u0026thinsp;0.05 was used to identify significant matches, corresponding to default algorithm parameters (e.g., match/mismatch scores and filter of low complexity regions) [\u003cspan citationid=\"CR35\" class=\"CitationRef\"\u003e35\u003c/span\u003e]. In this research, sequences were included if they represented verified closely related within \u003cem\u003eS. sinensim\u003c/em\u003e and \u003cem\u003eS. japonicum\u003c/em\u003e or within \u003cem\u003eS. japonicum\u003c/em\u003e itself for mitochondrial genes [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. These include the ND1 partial coding regions, ND1 complete coding regions, ND4 complete coding regions, COX3 partial coding regions, or complete mitochondrial genome. The resulting cladograms illustrated close evolutionary relationships among organisms, with the highest percentage match within each group indicating the inferred relationship. These data was used to determine the phylogenetic relationships of \u003cem\u003eS. japonicum\u003c/em\u003e from the Yangtze River Basin (Yunnan, Jiangxi, and Jiangsu) and to compare with isolates from other regions, including Japan, Indonesia, Taiwan, and the Philippines. In certain case, PhyML were used to support NCBI BLAST results.\u003c/p\u003e \u003cp\u003eIn this study, sequences were selected to reveal the evolutionary relationships of \u003cem\u003eS. sinensium\u003c/em\u003e (Sichuan, China) with \u003cem\u003eS. japonicum\u003c/em\u003e (China and Taiwan), using \u003cem\u003eS. indicum\u003c/em\u003e (Bangladesh) as an outgroup. These sequences were also used to investigate the evolutionary relationships of \u003cem\u003eS. japonicum\u003c/em\u003e from Jiangxi, China, by comparing them with isolates from other regions of China, Japan, Taiwan, the Philippines, and Indonesia. Sequences with less than 90% identity were identified as different species (\u003cem\u003eS. indicum, S. japonicum, S. malayensis, S. mekongi, S. ovuncatum\u003c/em\u003e, and \u003cem\u003eS. sinensium\u003c/em\u003e).\u003c/p\u003e \u003cp\u003eAll sequence data for \u003cem\u003eS. sinensium\u003c/em\u003e and \u003cem\u003eS. japonicum\u003c/em\u003e were sourced from the NCBI database. A tiered BLAST approach was used, where a standard megablast search was first performed, followed by a more sensitive BLASTn search if the results were nonsignificant [\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e]. Pairwise dot plots and the coding sequence (CDS) feature were employed to identify sequence differences. The analysis focused on determining the number of base and amino acid variations, which provides valuable insight into the genetic diversity \u003cem\u003eS. japonicum\u003c/em\u003e strains. Note that formal analyses for base substitutions and amino acid replacements were not conducted. A total of 84 mitochondrial sequences of \u003cem\u003eS. japonicum\u003c/em\u003e and \u003cem\u003eS. sinensium\u003c/em\u003e were included in the present study.\u003c/p\u003e \u003cdiv id=\"Sec3\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e2.1. Nucleotide BLAST for relationship between\u003c/em\u003e S. sinensium \u003cem\u003eand\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eFor this nucleotide BLAST analysis, reference sequences were obtained from the GenBank database at the NCBI. Sequences of the ND1 gene (including partial and CDS) and other mitochondrial DNA were used to investigate the relationships between \u003cem\u003eS. sinensium\u003c/em\u003e and \u003cem\u003eS. japonicum\u003c/em\u003e populations within the Yangtze River Basin, China. The accession numbers for the sequences are provided in Table \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e.\u003c/p\u003e \u003cp\u003eThe relatioonships between \u003cem\u003eS. sinensium\u003c/em\u003e and \u003cem\u003eS. japonicum\u003c/em\u003e were analyzed using nucleotide BLAST. The resulting percentage identities, E values, and slanted cladograms were used to compare sequences from provincies within the Yangtze River Basin (Yunnan, Jiangxi, and Jiangsu) and Taiwan. These data were analyzed to identify the \u003cem\u003eS. japonicum\u003c/em\u003e lineage most closely related to \u003cem\u003eS. sinensium.\u003c/em\u003e The branches of the slanted cladogram illustrate the rlationships among \u003cem\u003eS. japonicum\u003c/em\u003e poulations and their infection areas. \u003cem\u003eS. indicum\u003c/em\u003e was used as an outgroup to root the phylogenetic tree and infer evoultonary relationships. A total of 84 mitochondrial sequences of \u003cem\u003eS. japonicum\u003c/em\u003e and \u003cem\u003eS. sinensium\u003c/em\u003e were ultimately selected from GenBank and used for subsequent phylogenetic analyses.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec4\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e2.2. Relationships between the ND1 of\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eFor nucleotide BLAST analysis of \u003cem\u003eS. japonicum\u003c/em\u003e, reference sequences were obtained from the GenBank database (NCBI). Specifically, the complete mitochondrial ND1 CDS was retrieved. The GenBank data were sourced from the study by Yin et al. (2015) [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e], and the accession numbers are detailed in Table \u003cspan refid=\"MOESM2\" class=\"InternalRef\"\u003eS2\u003c/span\u003e.\u003c/p\u003e \u003cp\u003eNucleotide BLAST results were used to determine the phylogenetic relationships of \u003cem\u003eS. japonicum\u003c/em\u003e in the study regions. These results provided percentage identity, E value, and a slanted cladogram to visualize relationships among the isolates.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec5\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e2.3. Relationships between the ND4 gene of\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eFor nucleotide BLAST analysis, the complete mitochondrial ND4 CDS of \u003cem\u003eS. japonicum\u003c/em\u003e was obtained as a reference from GenBank (NCBI). The sequence data were sourced from the study by Yin et al. (2015) [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e] and included sequences from China, Japan, Indonesia, the Philippines, and Taiwan. The accession numbers for the sequences used in this analysis are listed in Table \u003cspan refid=\"MOESM3\" class=\"InternalRef\"\u003eS3\u003c/span\u003e.\u003c/p\u003e \u003cp\u003eThe percentage identity, E values, and a slanted cladogram derived from nucleotide BLAST were used to analyzed the phylogenetic relationships and infer the origin of \u003cem\u003eS. japonicum\u003c/em\u003e populations in China, Japan, Indonesia, the Philippines, and Taiwan.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec6\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e2.4. Relationships between the COX3 gene and mitochondria in\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eFor nucleotide BLAST analysis, reference sequences were accessed from the GenBank database at the NCBI. This dataset included both the partial COX3 CDS and complete mitochondrial genomes from various regions. Data were sourced from China, Indonesia, Japan, Taiwan and the Philippines. The accession numbers for all sequences used are detailed in Table \u003cspan refid=\"MOESM4\" class=\"InternalRef\"\u003eS4\u003c/span\u003e. .\u003c/p\u003e \u003cp\u003eThe phylogenetic relationships of \u003cem\u003eS. japonicum\u003c/em\u003e populations from China, Japan, Indonesia, Taiwan, and the Philippines were analyzed using nucleotide BLAST. Percentage identities and E values were obtained, and the resulting data were used to construct a slanted cladogram that visualizes the relationships between parasites from these regions. ClustalW and RaxML were used to obtain cladogram to be compared to cladogram of NCBI BLAST.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec7\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e2.5. Relationships among the complete mitochondrial genome of\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eReference sequences for the complete mitochondrial genome of \u003cem\u003eS.\u003c/em\u003e japonicum were obtained from the GenBank database at NCBI for nucleotide BLAST analysis. These data were originally published by Yin \u003cem\u003eet al.\u003c/em\u003e (2015) [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e] and include sequences from China, Japan, Indonesia, the Philippines, and Taiwan. The accession numbers for the sequences used in this study are provided in Table\u0026nbsp;5.\u003c/p\u003e \u003cp\u003eNucleotide BLAST results from the complete mitochondrial genome were used to determine the percentage identity, E value, and phylogenetic relationships of \u003cem\u003eS. japonicum\u003c/em\u003e populations across China, Japan, Indonesia, the Philippines, and Taiwan. The branches of the resulting cladogram illustrate the relationships among parasite populations in these regions.\u003c/p\u003e \u003c/div\u003e"},{"header":"3. Results","content":"\u003cdiv id=\"Sec9\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e3.1 Sequence analysis of\u003c/em\u003e S. sinensium \u003cem\u003eand\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003ePhylogenetic analyses were performed using 84 mitochondrial sequences of \u003cem\u003eS. japonicum\u003c/em\u003e and \u003cem\u003eS.\u003c/em\u003e sinensium across East and Southeast Asia. A BLASTn of the ND1 gene revealed that Sichuan \u003cem\u003eS. sinensium\u003c/em\u003e shares 73.23% identity with Taiwan \u003cem\u003eS. japonicum\u003c/em\u003e. Expanding on this, more sequences revealed that Taiwan \u003cem\u003eS. japonicum\u003c/em\u003e shares 96.87% identity with \u003cem\u003eS. japonicum\u003c/em\u003e fromYunnan, which represents the highest percentage found in mainland China. The analysis further detailed the close relationships between mainland China strains: Yunnan \u003cem\u003eS. japonicum\u003c/em\u003e shares 99.87% identity with the Sichuan strain, which, in turn, shares 99.61% identity with the Jiangxi and Anhui Guichi strains and 99.35% identity with the Hunan Changde strain. In contrast, Sichuan \u003cem\u003eS. sinensium\u003c/em\u003e displayed lower identity percentages with other strains: 72.29% with Anhui Guichi and Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e, 72.04% with Anhui Tongling \u003cem\u003eS. japonicum\u003c/em\u003e, and 71.79% with strains from Jiangsu, Sichuan, and Yunnan. The identity values for Hubei, Hunan Yueyang, and Hunan Changde \u003cem\u003eS. japonicum\u003c/em\u003e were 71.54%, 71.46%, and 71.28%, respectively, while the identity with Bangladesh \u003cem\u003eS. indicum\u003c/em\u003e was 75.00% (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, and Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). In addition, Sichuan \u003cem\u003eS. sinensium\u003c/em\u003e exhibited 106 base substitutions and 54 amino acid replacements compared to Jiangxi and Anhui Guichi \u003cem\u003eS. japonicum\u003c/em\u003e, and 107 base substitutions and 54 amino acid replacements compared to Anhui Tongling \u003cem\u003eS. japonicum.\u003c/em\u003e\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab1\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAccession, E-value and percentage of Schistosoma sinensium and\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"3\" nameend=\"c3\" namest=\"c1\"\u003e \u003cp\u003e\u003cem\u003eSchistosoma japonicum\u003c/em\u003e relationships for the ND1 gene\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSpecies\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eAccession\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eE-value\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eS. sinensium\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eAF465913.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFJ852203.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3e-53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.29%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793743.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e3e-53\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.29%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFJ852232.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4e-52\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e72.04%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFJ852250.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2e-50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71.79%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFJ852220.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2e-50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71.79%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFJ852216.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2e-50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71.79%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFJ852248.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2e-49\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71.54%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793758.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4e-51\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71.46%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eFJ852245.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e8e-48\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e71.28%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793776.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e6e-62\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e73.23%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. indicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNC_047240\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e2e-16\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e75.00%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS.: Schistosoma\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe cladogram (Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e) illustrates three main branches. The first branch, positioned separately from the others, includes \u003cem\u003eS. indicum\u003c/em\u003e from Bangladesh, \u003cem\u003eS. sinensium\u003c/em\u003e from Sichuan, \u003cem\u003eS. japonicum\u003c/em\u003e from Taiwan, and \u003cem\u003eS. japonicum\u003c/em\u003e from Hunan Yueyang. A second branch comprises \u003cem\u003eS. japonicum\u003c/em\u003e from Anhui Guichi, Jiangxi, Anhui Tongling, Jiangsu, Hubei, and Hunan Changde. The third branch is composed of \u003cem\u003eS. japonicum\u003c/em\u003e from Yunnan and Sichuan.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec10\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e3.2 Sequence analysis of the ND1 gene in\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eMegablast sequencing results for the mitochondrial ND1 gene (complete CDS) revealed a 100% identity between Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e and Hunan Changde \u003cem\u003eS. japonicum\u003c/em\u003e. A 99.89% identity was observed with \u003cem\u003eS. japonicum\u003c/em\u003e strains from Anhui Guichi, Anhui Tongling, Hunan Yueyang, Indonesia, the Philippines, and Yunnan. A comparison also showed that Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e shares 99.78% identity with Indonesian and Sichuan \u003cem\u003eS. japonicum\u003c/em\u003e, a 99.66% identity with Japanese \u003cem\u003eS. japonicum\u003c/em\u003e, a 99.55% identity with Hunan Yueyang \u003cem\u003eS. japonicum\u003c/em\u003e, a 99.44% identity with Hubei \u003cem\u003eS. japonicum\u003c/em\u003e, a 99.33% identity with another Indonesian \u003cem\u003eS. japonicum\u003c/em\u003e, and a 96.75% identity with Taiwan \u003cem\u003eS. japonicum\u003c/em\u003e. All resulting E values were 0.0 (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab2\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAccession, E value and percentage of Schistosoma japonicum\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003erelationships for the ND1 gene, complete CDS, mitochondrial\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSpecies\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eAccession\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eE-value\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eS. japonicum\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eKP793763.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793756.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793743.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.89%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793747.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.89%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793759.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.89%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793779.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.89%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793769.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.89%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793783.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.89%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793777.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.78%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793765.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.78%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793780.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.66%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793758.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.55%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793749.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.44%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793778.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.33%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793776.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e96.75%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. indicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNC_047240.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e4e-50\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e66.06%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS.: Schistosoma\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eThe cladogram (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e) shows that Yunnan and Taiwan \u003cem\u003eS. japonicum\u003c/em\u003e form a separate branch. Strains from Anhui Tongling and Sichuan are clustered together, as are \u003cem\u003eS. japonicum\u003c/em\u003e from Japan, Hunan, and Hubei. A comparison between Japanese \u003cem\u003eS. japonicum\u003c/em\u003e and Hunan Yueyang \u003cem\u003eS. japonicum\u003c/em\u003e showed 99.66% identity, with different three base substitutions but no amino acid replacements. When compared with Hubei \u003cem\u003eS. japonicum\u003c/em\u003e, it showed a 99.55% identity, with four base substituions and one amino acid replacement. In addition, Indonesian and Philippine \u003cem\u003eS. japonicum\u003c/em\u003e each had one base substitution relative to Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec11\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e3.3 Sequence analysis of the ND4 gene in\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eThe megablast analysis for the complete mitochondrial CDS, specifically the ND4 gene, revealed that Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e shares 99.92% identity with \u003cem\u003eS. japonicum\u003c/em\u003e from Sichuan and Yunnan. The identity with Anhui Guichi and Hunan Changde was 99.84%, and with Anhui Tongling \u003cem\u003eS. japonicum\u003c/em\u003e was 99.76%. Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e also showed 99.69% identity with Hunan Yueyang \u003cem\u003eS. japonicum\u003c/em\u003e, all Indonesian strains, and the Philippine strain. Further comparisons yielded an identity of 99.61% with Japan \u003cem\u003eS. japonicum\u003c/em\u003e; 99.45% with Hunan Yueyang \u003cem\u003eS. japonicum\u003c/em\u003e, 99.44% with Hubei \u003cem\u003eS. japonicum\u003c/em\u003e, and 97.73% with Taiwan \u003cem\u003eS. japonicum\u003c/em\u003e. All E values were 0.0 (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab3\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAccession, E value and percentage of Schistosoma japonicum\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"4\" nameend=\"c4\" namest=\"c1\"\u003e \u003cp\u003erelationships for the ND4 gene, complete CDS, mitochondrial\u003c/p\u003e \u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSpecies\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eAccession\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eE-value\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eS. japonicum\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eKP793805.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793807.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.92%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793811.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.92%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793785.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.84%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793798.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.84%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793789.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e).0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.76%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793801.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.69%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793819.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.69%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793820.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.69%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793821.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.69%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793825.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.69%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793822.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.61%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793800.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.45%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793791.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.37%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKP793818.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e97.37%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. indicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eNC_047240.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e9e-42\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e66.05%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS.: Schistosoma\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eBased on the cladogram and sequence analysis (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e), Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e forms a distinct, stand-alone branch. Japan \u003cem\u003eS. japonicum\u003c/em\u003e is clustered with Hunan Yueyang and Hubei \u003cem\u003eS. japonicum.\u003c/em\u003e Within this group, Japan \u003cem\u003eS. japonicum\u003c/em\u003e shares 99.69% identity with the Hunan Yueyang strain, differing by four base substitutions and two amino acid replacements. It shares 99.61% identity with the Hubei strain, a difference that includes five base substitutions and two amino acid replacements. In addition, Hunan Changde and Hunan Yueyang form a separate, distinct branch. Anhui Tongling \u003cem\u003eS. japonicum\u003c/em\u003e clusters with the Philippine and Indonesian strains, sharing 99.76% identity with both. Compared to all Indonesian \u003cem\u003eS. japonicum\u003c/em\u003e, it has three base substitutions and two amino acid replacements, while it has three base substitutions and one amino acid replacement when compared to the Philippine strain. Finally, Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e is grouped with the strains from Anhui Guichi, Sichuan, and Yunnan.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec12\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e3.4 Sequence analysis of the COX3 gene and complete mitochondrial genome in\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eMegablast results for the COX3 gene, partial mitochondrial CDS, and complete mitochondrial genome revealed that Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e shared 100% identity with strains from Sichuan, Anhui, and Jiangsu. It showed 99.83% identity with strains from Indonesia, Japan, the Philippines, Taiwan, Hunan, and Hubei, but only 96.65% identity with the Yunnan strain. All analyses yielded an E value of 0.0 (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, and Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e).\u003c/p\u003e \u003cp\u003e \u003cdiv class=\"gridtable\"\u003e\u003ctable float=\"Yes\" id=\"Tab4\" border=\"1\"\u003e \u003ccaption language=\"En\"\u003e \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e \u003cdiv class=\"CaptionContent\"\u003e \u003cp\u003eAccession, E-value and percentage of Schistosoma japonicum\u003c/p\u003e \u003c/div\u003e \u003c/caption\u003e \u003ccolgroup cols=\"4\"\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c1\" colnum=\"1\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c2\" colnum=\"2\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c3\" colnum=\"3\"\u003e\u003c/div\u003e \u003cdiv align=\"left\" class=\"colspec\" colname=\"c4\" colnum=\"4\"\u003e\u003c/div\u003e \u003cthead\u003e \u003ctr\u003e \u003cth align=\"left\" colspan=\"2\" nameend=\"c2\" namest=\"c1\"\u003e \u003cp\u003erelationships for the COX3 gene\u003c/p\u003e \u003c/th\u003e \u003cth align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/th\u003e \u003cth align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/th\u003e \u003c/tr\u003e \u003c/thead\u003e \u003ctbody\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cb\u003eSpecies\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003e\u003cb\u003eAccession\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e\u003cb\u003eE-value\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eS. japonicum\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e\u003cb\u003eEU927628.1\u003c/b\u003e\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEU927627.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEU927612.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEU927635.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e100%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eJQ781214.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.83%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eJQ781215.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.83%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKU196357.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.83%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eKF279410.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.83%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEU927625.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.83%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEU927619.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.83%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e \u003cp\u003eEU927638.1\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e \u003cp\u003e0.0\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e \u003cp\u003e99.65%\u003c/p\u003e \u003c/td\u003e \u003c/tr\u003e \u003ctr\u003e \u003ctd align=\"left\" colname=\"c1\"\u003e \u003cp\u003e\u003cem\u003eS.: Schistosoma\u003c/em\u003e\u003c/p\u003e \u003c/td\u003e \u003ctd align=\"left\" colname=\"c2\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c3\"\u003e\u0026nbsp;\u003c/td\u003e \u003ctd align=\"left\" colname=\"c4\"\u003e\u0026nbsp;\u003c/td\u003e \u003c/tr\u003e \u003c/tbody\u003e \u003c/colgroup\u003e \u003c/table\u003e\u003c/div\u003e \u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eAnalysis of the slanted cladogram revealed that the Jiangsu and Yunnan \u003cem\u003eS. japonicum\u003c/em\u003e sequences clustered on distinct branch. The Anhui Guichi and Taiwan strainss were grouped together, sharing 99.83% identity. The Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e strain clustered with the Japan, the Philippines, and Indonesia strains. A comparison showed that while the Jiangxi strain had one base pair substitution, it exhibited no corresponding amino acid replacement when compared to other three strains.\u003c/p\u003e \u003c/div\u003e \u003cdiv id=\"Sec13\" class=\"Section2\"\u003e \u003ch2\u003e\u003cem\u003e3.5 Sequence analysis of the complete mitochondrial genome of\u003c/em\u003e S. japonicum\u003c/h2\u003e \u003cp\u003eMegablast results for the complete mitochondrial genome revealed that Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e had varying degrees of identity with other strains (Table\u0026nbsp;5 and Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). The highest identity was observed with Anhui Tongling( 99.87%), followed by Hunan Yueyang (99.86%), Anhui Guichi, Indonesia, and the Philippines (99.82%); and Yunnan (99.81%). Lower identities were found with Sichuan (99.75%), Hubei (99.69%), Japan (99.40%), Hunan Yueyang (99.32%) and Taiwan (98.02%). All the E values were 0.0.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eIn the slanted cladogram, \u003cem\u003eS. japonicum\u003c/em\u003e from Taiwan formed, a distinct, stand-alone branch. The Japan strain was in the same group as the Hunan Yueyang strain, differing by 40 base substitutions and six amino acid replacements. A separate group included strains from Indonesia and te Philippines, Hunan Yueyang and Anhui Guichi. The Indonesian strain shared 99.89% identity with the Anhui Guichi strain, with 16 base substitutions and three amino acid replacements. The Indonesian strain also showed 99.80% identity with the Hunan Yueyang strain. Finally, the Philippine strain shared 99.87% identity with the Anhui Guuichi strain and 99.29% identity with the Hunan Yueyang strain, with 18 base substitutions and three amino acid replacements when compared to the Anhui Guichi strain.\u003c/p\u003e \u003c/div\u003e\u003cdiv\u003e\n \u003ctable border=\"0\" cellspacing=\"0\" cellpadding=\"0\" width=\"513\"\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" colspan=\"4\" valign=\"bottom\" style=\"width: 100%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eTable 5.\u0026nbsp;\u003c/strong\u003eAccession, E-value and percentage of\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003cem\u003eSchistosoma japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" colspan=\"3\" valign=\"bottom\" style=\"width: 73.6842%;\"\u003e\n \u003cp\u003erelationshipps for the mitochondrial comple genome\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpecies\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eAccession\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eE-value\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e\u003cstrong\u003e\u0026nbsp;\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e\u003cstrong\u003eKU196367.1\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196313.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.87%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196317.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.87%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196347.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.86%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196305.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196307.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196348.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196379.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.82%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196408.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.81%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196389.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.75%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196318.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.69%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196328.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.69%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196359.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.40%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196338.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e99.32%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. japonicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eKU196398.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e0.0\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e98.02%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS. indicum\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\n \u003cp\u003eNC_047240.1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\n \u003cp\u003e5e-150\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\n \u003cp\u003e75.14%\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 30.4094%;\"\u003e\n \u003cp\u003e\u003cem\u003eS.: Schistosoma\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 27.2904%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 15.9844%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003ctd nowrap=\"\" valign=\"bottom\" style=\"width: 26.3158%;\"\u003e\u003cbr\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n\u003c/div\u003e"},{"header":"4. Discussion","content":"\u003cp\u003e \u003cem\u003eS. sinensium\u003c/em\u003e diverged from \u003cem\u003eS.\u003c/em\u003e ovuncatum [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. Both \u003cem\u003eS. ovuncatum\u003c/em\u003e and \u003cem\u003eS. sinensium\u003c/em\u003e occur across China, India, and Thailand, reflecting their broad distribution within Asian schistosome lineages [\u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e]. Subsequently, \u003cem\u003eS. japonicum\u003c/em\u003e diverged from \u003cem\u003eS. sinensium\u003c/em\u003e, followed by divergence of \u003cem\u003eS. mekongi\u003c/em\u003e and \u003cem\u003eS. malayensis\u003c/em\u003e from \u003cem\u003eS. japonicum\u003c/em\u003e [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e]. \u003cem\u003eS. japonicum\u003c/em\u003e represents one of five species within this lineage, alongside \u003cem\u003eS. ovuncatum, S. sinensium, S. mekongi\u003c/em\u003e, and \u003cem\u003eS. malayensis\u003c/em\u003e [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e]. Unlike its intermediate host genus \u003cem\u003eOncomelania\u003c/em\u003e, believed to originate from eastern Indonesia, \u003cem\u003eS. japonicum\u003c/em\u003e spread from Chinese lake regions to East and Southeast Asia [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Consistent phylogenetic evidence indicates that \u003cem\u003eS. japonicum\u003c/em\u003e remains closely related to \u003cem\u003eS. sinensium\u003c/em\u003e within the broader Asian schistosome evolutionary lineage [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e\u0026ndash;\u003cspan citationid=\"CR38\" class=\"CitationRef\"\u003e38\u003c/span\u003e].\u003c/p\u003e \u003cp\u003ePrevious study suggested that \u003cem\u003eS. japonicum\u003c/em\u003e populations form four primary clades located in mainland Chinese, Indonesia, the Philippines, and Taiwan [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e genetically distinct from other regional populations and diverged approximately forty-five thousand years ago [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Later divergence events occurred more recently, with Philippine populations separating from Chinese lake regions approximately seven thousand five hundred years ago. Subsequently, Sichuan and Yunnan populations diverged roughly five thousand four hundred years ago from earlier mainland Chinese ancestral lineages [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Indonesia and Japanese \u003cem\u003eS. japonicum\u003c/em\u003e populations diverged from Chinese populations approximately five thousand years ago, reflecting later regional dispersal events. Some researchers therefore proposed that Taiwanese and Southeast Asian populations could represent subspecies within the broader \u003cem\u003eS. japonicum\u003c/em\u003e lineage [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Notably, Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e exhibits zoophilic behavior but lacks zoonotic transmission potential, distinguishing it from other regional populations [\u003cspan citationid=\"CR40\" class=\"CitationRef\"\u003e40\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSequence analyses conducted in this study indicate that \u003cem\u003eS. japonicum\u003c/em\u003e diverged from \u003cem\u003eS. sinensium\u003c/em\u003e in Taiwan, followed by additional divergences events in Anhui Guichi and Jiangxi populations. Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e exhibits greater genetically similarity to Yunnan strains than to several other mainland Chinese populations examined here. The Taiwanese strain shares 96.87% sequence identity with Yunnan \u003cem\u003eS. japonicum\u003c/em\u003e, suggesting potential historical evolutionary connections between these regions. Yunnan strains display extremely high identity, approximately 99.87%, with \u003cem\u003eS. japonicum\u003c/em\u003e populations from Sichuan, Anhui Guichi, and Jiangxi lake regions. High identity values between Yunnan and lake-region strains suggest eastward parasite dispersal from southwestern China toward central and eastern regions. This pattern agrees with Young \u003cem\u003eet al.\u003c/em\u003e (2015) [\u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e], who reported eastward spread forming central and eastern Chinese population group [\u003cspan citationid=\"CR21\" class=\"CitationRef\"\u003e21\u003c/span\u003e, \u003cspan citationid=\"CR22\" class=\"CitationRef\"\u003e22\u003c/span\u003e]. \u003cem\u003eS. sinensium\u003c/em\u003e shares approximately 72% identity with Anhui Guichi and Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e populations examined in this study. Approximately 73% identity was also observed between \u003cem\u003eS. sinensium\u003c/em\u003e and Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e, supporting their deeper evolutionary divergence (Table\u0026nbsp;\u003cspan refid=\"Tab1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e, and Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). Previous research suggested that \u003cem\u003eS. japonicum\u003c/em\u003e spread from Anhui Guichi and Jiangxi lake regions toward mainland China, Japan, Indonesia, and the Philippines [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSequence comparisons indicate that Sichuan \u003cem\u003eS. sinensium\u003c/em\u003e shows closer genetic affinity to Anhui Guichi and Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e than to Anhui Tongling populations. Sichuan \u003cem\u003eS. japonicum\u003c/em\u003e displays 54 amino acid replacements relative to Anhui Guichi, Anhui Tongling, and Jiangxi populations. These patterns suggest strong genetic relatedness among Sichuan, Anhui Guichi, and Jiangxi \u003cem\u003eS. japonicum\u003c/em\u003e strains. Evidence further indicates that Anhui Guichi and Jiangxi populations subsequently dispersed toward Anhui Tongling, Hubei, Jiangsu, Hunan, Yunnan, and Sichuan.\u003c/p\u003e \u003cp\u003eThe present findings also suggest increased prevalence of \u003cem\u003eS. japonicum\u003c/em\u003e specifically within Anhui Guichi and Jiagxi lake regions. Earlier research did not clearly identify this geographic concentration of parasite populations within mainland China [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Phylogenetic evidence further suggests that Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e populations represent older lineages relative to mainland Chinese populations. These results also support earlier conclusions that divergence of \u003cem\u003eS. japonicum\u003c/em\u003e from \u003cem\u003eS. sinensium\u003c/em\u003e occurred relatively early in Asian schistosome evolution [\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e, \u003cspan citationid=\"CR37\" class=\"CitationRef\"\u003e37\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eND1 gene sequences reveal complete identity between Jiangxi and Hunan Changde \u003cem\u003eS. japonicum\u003c/em\u003e populations examined in this study (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Other mainland Chinese, Japanese, Indonesian, and Philippine populations show slightly lower identities ranging from 99.55% to 99.89%. These findings indicate that Southeast Asian and Japanese populations retain extremely close genetic relationships with mainland Chinese \u003cem\u003eS. japonicum\u003c/em\u003e. Hunan Changde and Jiangxi strains share approximately 97% identity with Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e, representing the lowest similarity among Asian strains examined.\u003c/p\u003e \u003cp\u003eThe ND1 cladogram further shows that Taiwanese and Yunnan \u003cem\u003eS. japonicum\u003c/em\u003e form a distinct phylogenetic branch (Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Anhui Tongling and Sichuan populations cluster within the same group, indicating strong genetic similarity between these regional populations. Japanese \u003cem\u003eS. japonicum\u003c/em\u003e clusters with Hunan Yueyang and Hubei strains within the same phylogentic group. Japanese and Hunan Yueyang sequences display no amino acid replacements, whereas comparisons with Hubei reveal a single replacement. These findings suggest that Japanese \u003cem\u003eS. japonicum\u003c/em\u003e likely originated from populations related to Hunan Yueyang lineage.\u003c/p\u003e \u003cp\u003eAll Indonesian and Philippine \u003cem\u003eS. japonicum\u003c/em\u003e strains cluster together within the same phylogenetic group based on the ND1 gene sequences (Table\u0026nbsp;\u003cspan refid=\"Tab2\" class=\"InternalRef\"\u003e2\u003c/span\u003e and Fig.\u0026nbsp;\u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). Indonesian populations share extermely high identity values between 99.44% and 99.89% with Jiangxi strains from mainland China. These results indicate that Southeast Asian populations likely originated from either Hunan Changde or Jiangxi ancestrl lineages. Sequence alignments show only one base substitution and amino acid replacements relative to Hunan Changde or Jiangxi strains. Previous reports suggested that Philippine lineages diverged first from Chinese lake populations before iving rise to Indonesian and Japanese lineages [\u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eND4 gene analyses indicate relatively low genetic divergence among mainland Chinese \u003cem\u003eS. japonicum\u003c/em\u003e populations examined in this study. Jiangxi populations share greater than 99% identity with most mainland Chinese, Japanese, Indonesian, and Philippine strains (Table\u0026nbsp;\u003cspan refid=\"Tab3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). These findings contrast with previous reports suggesting higher genetic divergence among Chinese \u003cem\u003eS. japonicum\u003c/em\u003e populations [\u003cspan citationid=\"CR32\" class=\"CitationRef\"\u003e32\u003c/span\u003e, \u003cspan citationid=\"CR39\" class=\"CitationRef\"\u003e39\u003c/span\u003e]. Taiwanese populations show approximately 98% identity with Jinagxi populations, confirming deeper divergence from mainland Chinese strains.\u003c/p\u003e \u003cp\u003eND4 cladogram analyses further indicate that Japanese \u003cem\u003eS. japonicum\u003c/em\u003e populations likely derived from Hunan Yueyang populations in central China. Japanese strains display similar amino acid replacements to those observed in Hunan Yueyang and Hubei populations (Fig.\u0026nbsp;\u003cspan refid=\"Fig3\" class=\"InternalRef\"\u003e3\u003c/span\u003e). However, Japanese strains show fewer base substitutions relative to Hunan Yueyang than to Hubei strains. These results further support a potential Hunan Yueyang origin for Japanese \u003cem\u003eS. japonicum\u003c/em\u003e populations.\u003c/p\u003e \u003cp\u003eAnhui Tongling populations share approximately 99.76% identity with Southeast Asian strains from Indonesia and the Philippines. Philippines strains shows one amino acid replacement relative to Anhui Tongling, whereas Indonesia strains exhibit two replacements. These findings suggests that Southeast Asian populations likely originated from Anhui Tongling ancestral lineages in mainland China. Identity values further suggest that Philippine populations diverged first, followed by Indonesian and Japanese populations.\u003c/p\u003e \u003cp\u003eAnalyses of COX3 gene sequences and complete mitochondrial genomes further clarify phylogenetic relationships among regional populations. Taiwanese populations shares 99.83% identity with Anhui Guichi and Jiangxi strains (Table\u0026nbsp;\u003cspan refid=\"Tab4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, Fig.\u0026nbsp;\u003cspan refid=\"Fig4\" class=\"InternalRef\"\u003e4\u003c/span\u003e, and Figure \u003cspan refid=\"MOESM1\" class=\"InternalRef\"\u003eS1\u003c/span\u003e). These findings suggest that Taiwanese populations may have originated from mainland Chinese populations. Jiangxi, Japanese, Indonesian, and Philippine populations cluster within the same phylogenetic group in mitochondrial analyses. Extremely high identity values and minimal amino acid replacements indicate recent divergence among these regional populations.\u003c/p\u003e \u003cp\u003eComplete mitochondrial genome analyses further support relationships observed in gene-specific phylogenetic reconstructions. Japanese populations cluster closely with Hunan Yueyang strains, supporting previous interpretations of their evolutionary origin (Fig.\u0026nbsp;\u003cspan refid=\"Fig5\" class=\"InternalRef\"\u003e5\u003c/span\u003e). Indonesian populations cluster with Hunan Yueyang, Anhui Guichi, and Philippine populations in the same phylogenetic group. Lower substitution numbers relative to Anhui Guichi strains suggest ancestral relationships linking Southeast Asian populations with Chinese lake-region lineages.\u003c/p\u003e \u003cp\u003eMitochondrial analyses overall indicate that Japanese populations likely originated from central Chinese provinces including Hunan and Hubei. Southeast Asian populations were compared with strains from Anhui Guichi, Anhui Tongling, Hunan Changde, and Jiangxi. Results demonstrate extremely close genetic relationships among Chinese, Japanese, and Southeast Asian populations. However, Taiwanese populations form a distinct lineage that diverged earlier from other regional populations.\u003c/p\u003e \u003cp\u003eGenetic studies also reveal that several Indonesian ethnic groups possess ancestral connections with populations from China or Taiwan [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]. These migrations occurred approximately three to four thousand years ago and may have facilitated parasite dispersal [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e]. Archaeological evidence from megalithic cultural traditions in Central Sulawesi further supports ancient migration patterns within this region [\u003cspan citationid=\"CR41\" class=\"CitationRef\"\u003e41\u003c/span\u003e]. These patterns suggest that \u003cem\u003eS. japonicum\u003c/em\u003e in Lore Lindu National Park may have been introduced from southern China approximately four thousand years ago [\u003cspan citationid=\"CR23\" class=\"CitationRef\"\u003e23\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAnalyses of mitochondrial genome sequences, including ND1, ND4, COX3, and complete mitochondrial genomes, indicate that Japanase \u003cem\u003eS.\u003c/em\u003e japonicum likely originated from Hunan and Hubei provinces. Comparative analyses of Southeast Asia and Chinese isolates further demonstrate close genetic relationships, with the exception of the distinct Taiwanese lineage. These findings provide new insights into the phylogeographic structure and historical patterns of \u003cem\u003eS. japonicum\u003c/em\u003e across East and Southeast Asia. Although this study analyzed 84 mitochondrial sequences using robust phylogenetic approaches, the absence of nuclear genetic markers may limit resolution of deeper evolutionary relationships. Overall, the results contribute to a better understanding of parasite evolution and regional transmission dynamics.\u003c/p\u003e"},{"header":"5. Conclusions","content":"\u003cp\u003eStudies on \u003cem\u003eSchistosoma\u003c/em\u003e species reveal several key genetic relationships and dispersal patterns. The Sichuan \u003cem\u003eS. sinensium\u003c/em\u003e lineage was the first to diverge into what is the Taiwanese \u003cem\u003eS. japonicum\u003c/em\u003e. The Taiwanese population itself is a mix of the original strain and lineage from mainland China. In mainland China, the Yunnan \u003cem\u003eS. japonicum\u003c/em\u003e population diversified, giving rise to the Sichuan, Anhui Guichi, and Jiangxi strains, which subsequently spread through the Far East, including Japan, the Philippines, Indonesia, and Taiwan. Specifically the Japanese \u003cem\u003eS. japonicum\u003c/em\u003e strain originated from the Anhui Guichi, Hunan Yueyang, and Jiangxi. Similarly, the Southeast Asian \u003cem\u003eS. japonicum\u003c/em\u003e strains are descendants of Chinese populations from Anhui Tongling, Anhui Guichi, Hunan Changde, and Jiangxi. Overall, the genetic evidence confirms a close relations between \u003cem\u003eS. japonicum\u003c/em\u003e strains found in Japan and Southeast Asia and those in China.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAcknowledgments\u003c/strong\u003e\u003cstrong\u003e:\u0026nbsp;\u003c/strong\u003eDuring the preparation of this work the author used ChatGPT for improving clarity, readability, and textual overlap with previously published works. After using these services, the author reviewed and edited the content as needed and take full responsibility for the content of the published article.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions:\u0026nbsp;\u003c/strong\u003eConceptualization, M.N; methodology, M.N; validation, M.N.; formal analysis, M.N.; investigation, M.N.; data curation, M.N.; writing\u0026mdash;original draft preparation, M.N.; writing\u0026mdash;review and editing, M.N.; visualization, M.N.; supervision, M.N.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003cstrong\u003e:\u0026nbsp;\u003c/strong\u003eThis study did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eData availability:\u0026nbsp;\u003c/strong\u003eAll the data generated or analyzed durig this study are included in this published article [and its supplementary information file].\u0026nbsp;\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConflict of interest\u003c/strong\u003e\u003cstrong\u003e:\u0026nbsp;\u003c/strong\u003eThe author declares no conflict of interest.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eInformed consent statement:\u0026nbsp;\u003c/strong\u003eNot applicable.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eAttwood, S. 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Megalithic cultural heritage of Lore Lindu area, July (2025). \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://whc.unesco.org/en/tentativelists/6826\u003c/span\u003e\u003cspan address=\"https://whc.unesco.org/en/tentativelists/6826\" targettype=\"URL\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e (accessed 11.\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Oncomelania, Schistosoma sinensium, Schistosoma japonicum, Schistosomiasis japonica","lastPublishedDoi":"10.21203/rs.3.rs-9212654/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9212654/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe evolutionary relationships and geographic differentiation of \u003cem\u003eSchistosoma japonicum\u003c/em\u003e populations across East and Southeast Asia remain incompletely resolved. This study investigated phylogenetic structure and regional dispersal patterns using mitochondrial genomes and ND1, ND4, and COX3 gene sequences from 84 isolates. Phylogenetic reconstruction revealed clear divergence between \u003cem\u003eS. japonicum\u003c/em\u003e and \u003cem\u003eS. sinensium\u003c/em\u003e, supporting their distinct evolutionary positions within the Asian schistosome lineage. Comparative analyses further identified pronounced genetic differentiation between Chinese populations and isolates form Taiwan. ND1 sequence comparations demonstrated extremely high genetic identity exceeding 99% among strains from China, Japan, Indonesia, and the Philippines. These results indicate strong genetic continuity among geographically distant populations despite wide regional separation. Phylogeographic patterns support a mainland Chinese origin followed by historical dispersal toward Japan and Southeast Asian archipelagos. These findings provide new insights into the evolutionary history and regional dissemination pathways of \u003cem\u003eS. japonicum\u003c/em\u003e across East and Southeast Asia.\u003c/p\u003e","manuscriptTitle":"Phylogeographic structure and historical dispersal of Schistosoma japonicum across East and Southeast Asia","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-01 05:17:28","doi":"10.21203/rs.3.rs-9212654/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-23T17:29:20+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-23T09:30:17+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-16T02:17:37+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"84300650733204665591253719860884432280","date":"2026-04-09T16:00:31+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"83805198384227465730114925297045106568","date":"2026-04-02T05:20:36+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"80187944489684029678834941188042284123","date":"2026-04-02T03:30:22+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-31T15:46:15+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-31T15:08:23+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-25T11:08:44+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-25T11:08:19+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2026-03-24T13:29:55+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ec1150f8-7919-4319-b79f-4f5246cbf0b7","owner":[],"postedDate":"April 1st, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":65496040,"name":"Biological sciences/Ecology"},{"id":65496041,"name":"Earth and environmental sciences/Ecology"},{"id":65496042,"name":"Biological sciences/Evolution"},{"id":65496043,"name":"Biological sciences/Genetics"},{"id":65496044,"name":"Biological sciences/Microbiology"}],"tags":[],"updatedAt":"2026-05-12T10:06:51+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-01 05:17:28","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9212654","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9212654","identity":"rs-9212654","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}