Clinical, Biochemical and Molecular Characterizations of Patients With Glutaric Aciduria Type 1 in Henan Province, China

Clinical, Biochemical and Molecular Characterizations of Patients With Glutaric Aciduria Type 1 in Henan Province, China | 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 Research Article Clinical, Biochemical and Molecular Characterizations of Patients With Glutaric Aciduria Type 1 in Henan Province, China Xinyun Zhu, Xiaole Li, Suna Liu, Min Ni, Yaqing Guo, Yizhuo Xu, and 3 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-1274419/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Background: Glutaric acidemia type 1 (GA1) is a rare organic acid metabolism disorder resulted from the deficiency of glutaryl-CoA dehydrogenase (GCDH). There are few studies on GA1 in China. This article is designed to investigate the clinical, biochemical and molecular characterizations of patients with GA1 in Henan province, in order to get further understanding of this disease . Results: The incidence of neonatal GA1 in Henan population was 1/172483. All patients had increased glutarylcarnitine (C5DC), glutaric acid (GA) and 3-hydroxyglutaric acid (3-OH-GA) levels. Twenty mutations were discovered in 14 patients. Four of them were novel: c.523G>A (p.G175S), c.1297G>C (p.A433P), c.467G>A (p.G156D) and c.1125T>G (p.C375W). The most common mutation was c.1064G>A (p.R355H), of which the allelic frequency was 17.86% (5/28), following by c.1109T>C (p.L370P), c.648G>A (p.S216S), c.395G>A (p.R132Q) and c.938G>A (p.R313Q), which had the same allelic frequency 7.14% (2/28). 84.6%(11/13) patients displayed abnormal brain MRI findings, of which cerebral dysplasia and arachnid/ependyma cysts(38.5%,5/13) were most commonly. Clinical features varied widely from asymptomatic to severe encephalopathy. Patients diagnosed by newborn screening had better outcome. A strong correlation was discovered among increasing disability in motor, speech and cognitive function. There were statistical significance differences in motor function(p=0.024) and speech function (p=0.008), but no statistical significance difference in cognitive function (p=0.106) between NBS group and non-NBS group. Conclusions: Our study provided comprehensive information about GA1 in Henan population, including morbidity, clinical, biochemical, molecular and outcome features. The novel variants expanded the GCDH variant spectra. This work emphasize that professional management of NBS programs and experienced genetic metabolic disease experts will be very important and urgent. Glutaric aciduria type 1 GCDH gene glutarylcarnitine restricted protein diet mutations Figures Figure 1 Background Glutaric aciduria type 1 (GA1, OMIM#231670) is a rare autosomal recessive metabolism disorder that caused by glutaryl-CoA dehydrogenase (GCDH) deficiency. This enzyme activity is remarkable decreased because of variants in encoding GCDH gene which locates on chromosome 19p13.2. in the metabolism process of lysine, hydroxylysine, and tryptophan, the ability which transforms glutaryl-CoA to crotonylCoA is decreased. Thus leading to an abnormal accumulation of glutarylcarnitine (C5DC),glutaric acid (GA) and 3-hydroxyglutaric acid (3-OH-GA) in a variety of body tissues, especially in brain[ 1 ]. Estimated worldwide prevalence of GA1 is 1 in 110,000 newborns[ 2 ].In China, the nationwide incidence of GA1 is between 1/171,411 and 1/52,078[ 3 , 4 ]. It has been reported that the incidence of GA1 in Quanzhou, a south region of China, was 1 in 47,044 newborns[ 5 ]. The clinical features and severity of GA1 patients were significantly different. Some patients are asymptomatic whereas some appear neurological symptoms such as dystonia, dyskinesia, hypotonia and motor disability. The clinical features mainly include macrocephaly, developmental regression, acute encephalopathy, which is often triggered by fever, infection, vaccination or surgery, accompanying by seizures, cerebral dysplasia ,subdural effusion and cyst[ 1 , 6 ]. Treatment strategy of GA1 includes restricted protein with low lysine/tryptophan diet, L-carnitine and emergency treatment[ 2 ]. Because of lacking typical features before acute encephalopathic crisis or latent onset, early diagnosis becomes difficult. Early diagnosis and treatment can effectively reduce the occurrence of encephalopathic crises[ 6 , 7 ]. Biochemical changes including increased C5DC, glutaric acid (GA) and 3-hydroxyglutaric acid3-OH-GA) can be detected by tandem mass spectrometer and gas chromatography-mass spectrometry.GA1 has been brought into a variety of national newborn screening (NBS) panels[ 8 ]. Early diagnosis through NBS is vital to achieve a better outcome[ 9 , 10 ]. Since first reported in 1975[ 11 ], more than 250 mutations have been described in the Human Gene Mutation Database (HGMD: www.hgmd.cf.ac.uk ). Some common variants have been identified, including c.*165A > G in Egyptian patients[ 12 ]p. Leu340Phe in Turkish patients[ 13 ] c.1244-2A > C in Chinese patients[ 14 ]. In Henan, a middle region of China, newborn screening for GA1 has been performed since 2013. However, there are rare reports focusing on GA1 in Henan province. Data about the prevalence, NBS experience, variant spectrum and clinical manifestations in Henan are unclear. In this research, we investigated the clinical, biochemical, molecular characterizations and outcome of 16 GA1 patients in Henan province. This research aims to improve our further understanding characteristics about GA1 in Henan province. Results 1.incidence of GA1 in Henan During January 2013 to December 2021,1 034 896 newborns received screening at the Third Affiliated Hospital of Zhengzhou University and 6 newborns were confirmed with GA1. The incidence of GA1 in Henan population was 1 in 172 483 newborns. 2.Biochemical features The screening results of all patients showed increased C5DC level that ranged from 0.34 to 5.79 µmol/L (reference value: 0.01–0.27 µmol/L). The mean C5DC value were 1.91 ± 1.66 µmol/L. Urine GC/MS analysis showed elevated excretions of GA and 3-OH-GA in all patients. 3.Molecular genetics analysis Molecular genetics analysis was available in 14 patients. Twenty mutations were discovered in the 14 patients, including 18 missense mutations, a splicing mutation and a frameshift deletion (Table 1 ). All patients had compound heterozygous mutations. The most common mutation was c.1064G > A (p.R355H), of which the allelic frequency was 17.86% (5/28), following by c.1109T > C (p.L370P), c.648G > A (p.S216S), c.395G > A (p.R132Q) and c.938G > A (p.R313Q), and they had the same allelic frequency 7.14% (2/28). Among the twenty mutations, sixteen mutations have been reported previously and four variants were identified as novel by our team, namely c.523G > A (p.G175S), c.1297G > C (p.A433P), c.467G > A (p.G156D) and c.1125T > G (p.C375W). The four novel variants have no descriptions in the available databases. Novel variants of GCDH were shown in Fig. 1. However, c.467G > A was located in a highly homologous region and belonged to a special gene structure. Due to the limitation of Sanger detection technology, this locus failed to be verified by Sanger for many times. In silico analyses, the four novel variants had the PolyPhen2 values 1, 0.997, 1 and 1 respectively, suggesting probably damaging. Mutation Taster analyses presented that all the four variants are disease-causing. SIFT and REVEL analyses both showed that all the novel variants are damaging. Table 1 Biochemical and molecular features of 16 GA1 patients Patients NO. C5DC(µmol/L) Urinary GA and 3-OH-GA Genotype Type of mutation REVEL prediction Allele 1 Allele 2 Allele 1 Allele 2 Allele 1 Allele 2 N1 1.12 Elevated c.1064G > A(p.Arg355His) c.481C > G(p.Arg161Gly) missense missense Damaging Damaging N2 1.29 Elevated c.1109T > C(p.Leu370Pro) c.648G > A(p.Ser216Ser) missense missense Damaging - N3 5.79 Elevated c.533G > A(p.Gly178Glu) c.1064G > A(p.Arg355His) missense missense Damaging Damaging N4 2.47 Elevated c.523G > A(p.Gly175Ser) c.1297G > C(p.Ala433Pro) missense missense Damaging Damaging N5 0.34 Elevated c.1242A > C(p.Glu414Asp) c.395G > A(p.Arg132Gln) missense missense Damaging Damaging N6 3.91 Elevated NA NA NA NA NA NA C1 0.43 Elevated c.1109T > C(p.Leu370Pro); c.648G > A(p.Ser216Ser) missense missense Damaging - C2 0.83 Elevated c.1240G > A(p.Glu414Lys) c.938G > A(p.Arg313Gln) missense missense Damaging Damaging C3 2.43 Elevated c.937C > T(p.Arg313Trp) c.1064G > A(p.Arg355His) missense missense Damaging Damaging C4 2.25 Elevated c.395G > A(p.Arg132Gln) c.956 + 2T > A(p. ?) missense splicing Damaging NA C5 0.69 Elevated c.1240G > T(p.Arg402Trp) c.467G > A(p.Gly156Asp) missense missense - Damaging C6 0.92 Elevated c.938G > A(p.Arg313Gln); c.1233delC(p.Asp411Kfs*12) missense frameshift deletion Damaging NA C7 0.88 Elevated c.1064G > A(p.Arg355His) c.892G > A(p.Ala298Thr) missense missense Damaging Damaging C8 1.39 Elevated c.1064G > A(p.Arg355His) c.1125T > G(p.Cys375Trp) missense missense Damaging Damaging C9 0.8 Elevated NA NA NA NA NA NA C10 5.04 Elevated c.1204C > T(p.Arg402Trp) c.640A > G(p.Thr214Ala) missense missense Damaging Damaging C5DC: glutarylcarnitine,GA: glutaric acid, 3HGA: 3-hydroxyglutaric acid,REVEL :rare exome variant ensemble learner,NA: not available. 4.Clinical findings Clinical features of 16 patients are summarized below (Table 2 ). Two patients were failure to visit. Of the rest 14 patients, 2 patients were asymptomatic and 12 patients were symptomatic. The 12 patients with clinical symptoms had a median age 2.5 months (range: 0–12 months) at onset of symptoms and a median age 6.5 months at diagnosis (range: 20 days − 10 years). Patients N1-N6 were diagnosed through newborn screening. Patients C1-C10, who didn’t receive newborn screening, were symptomatic and clinical diagnosed with GA1. Table 2 Clinical features of 16 GA1 patients Patients NO. Gender Current age Age at onset Age at first screening Age at diagnosis Clinical symptoms Trigger events MRI brain findings Note N1 F NA NA 13D 20D NA NA NA Loss to follow-up N2 F 4Y2M - 20D 39D - - normal Asymptomatic N3 M 5Y2M 30D 25D 50D Macrocephaly - Bilateral temporal arachnid cysts, subependymal cysts - N4 F 1Y3M Fetal period 3D 34D Dystonia, Retardation - ependymal cyst - N5 M 2Y7M - 5D 35D - - normal - N6 F Died NA 16D NA NA NA NA Died C1 F 14Y 3M 10Y 10Y1M Regression,Limb soft,seizure fever Cerebral dysplasia - C2 M 3Y2M 27D 27D 9M Bucking,feeding difficulty,Dystonia, Limb soft - basal ganglia abnormal sign - C3 M 4Y1M 42D 3M 4M Dystonia, Retardation - NA - C4 F 4Y6M 6M 7M 8M Macrocephaly, seizure,Dystonia, regression vaccination Subdural effusion, Cerebral dysplasia - C5 F 6Y11M 1Y 1Y6M 1Y7M Regression, Dystonia fever arachnoid cyst, Cerebral dysplasia - C6 F 3Y11M 1Y 1Y 1Y1M Regression, dysphagia, feeding difficulty injury cysts, brain effusion - C7 F 8Y2M 2M 6M 6.5M Dystonia, Retardation - basal ganglia abnormal sign - C8 M 4Y3M Fetal period 5M 6M Macrocephaly, seizure,Dystonia, Bucking,Retardation,Metabolic acidosis - Hydrocephaly, Cerebral dysplasia - C9 M 5Y10M 3M 1Y3M 1Y4M Dystonia, Irritable - Cerebral dysplasia, Diffuse abnormal signals in bilateral white matter - C10 M 7Y8M 1Y 3Y6M 3Y7M Dystonia, Retardation - arachnoid cyst - M: male, F: female, NA: not available. 4.1.Newborn screening group Among six NBS patients, N2 and N5 were asymptomatic. N1 refused to accept treatment or follow-up after diagnosis and current status was unknown. N3 had macrocephaly as the main clinical feature. His head circumference was 49cm at the age of 6 months, but movement and intelligence developments were normal. N4 was detected to has ependymal cyst during fetal period and received newborn screening at 72 hours after birth and then she was diagnosed with GA1. She suffered from moderate movement disorder, mild speech disorder but with normal intelligence. N6 showed extremely high level of C5DC(3.91µmol/L, reference value: 0.01–0.27) in blood and GA (1919 mmol/molcreatinine, reference value:<2.5 ) in urine. Unfortunately, she was dead before the molecular genetics analysis. 4.2.Non-Newborn screening group C1, sibling of N2, presented convulsion and developmental regression because of fever at the age of six months but was misdiagnosed as encephalitis. She was finally diagnosed with GA1 at ten years old, thanking to her little sister's screening result. C2 presented bucking, feeding difficulty, limb soft and dystonia. At the age of 20 days, his blood sample was sent to an illegal medical laboratory and the result was abnormal. Unfortunately, because of lacking metabolic specialist, the doctor on basic hospital was unable to make the right diagnosis. Until at the age of 9 months, he was transferred to our hospital and was diagnosed with GA1. Besides, he had an older brother who died from encephalopathy crisis. C3 was born at 36 weeks of gestational age and showed dystonia. At 4 months of age, he was referred to our center and diagnosed with GA1. C4,C5 and C6 showed developmental regression because of fever, vaccination or tumble. In addition, C4 presented macrocephaly, seizure, dystonia and C6 presented dysphagia, feeding difficulty at the same time. C7 had dystonia and severe motor disability and was diagnosed with GA1 when she was 6.5 months old. C8 had enlarged head circumference in utero, which was discovered from prenatal ultrasound at 5 months of gestational age. Postnatal clinical manifestations were macrocephaly, seizure, dystonia, bucking, neurodevelopmental lag and metabolic acidosis, but he was failed to screen in time and was treated as hypoxic-ischemic encephalopathy. Until referred to our hospital at 5 months old, he was finally diagnosed with GA1. Similarly, patients C9 and C 10 showed dystonia, irritable and retardation at on set but were diagnosed accurately till the age of 1.3 years and 3.6 years respectively. 5.MRI findings The research acquired 13 patients’ brain MRI data. 11 patients( 84.6%) displayed abnormal and 2 patients (15.4%)displayed normal .The mainly abnormal findings were cerebral dysplasia (5/11, 45.5%), arachnid/ependymal cysts (5/11, 45.5%), following by basal ganglia abnormal sign (2/11, 18.2%), subdural effusion (1/11, 9.1%), hydrocephaly (1/11, 9.1%) and abnormal bilateral white matter (1/11, 9.1%). 6.Follow-up and outcome All patients got appropriate treatment immediately. As for the available 14 patients, we make regular follow-up visit until December 2021. Current age of these patients ranges from 15 months to 14 years (median age: 53 months). Four patients diagnosed by NBS have basically normal developments. N2 and N5 have normal development and already attended the kindergarten. N3 also has normal developments and the macrocephaly has been improved. N4 present normal speech and intelligence development but moderate motor disability. Four clinical patients(C1,C3,C5,C10)who were diagnosed by expanded screening, got notable improvements after treatment and three of them(C3,C5,C10) are able to attend the kindergarten or primary school. As for C1, intelligence function trends to normal but she remains moderate motor and speech retardation. On the contrary, six patients(C2,C4,C6-C9) received recommended treatment immediately after diagnosis but got no significant improvement and keep severe brain retardation. They are still unable to walk, speech or move. In addition, patient C8 suffers from hydrocephaly and recurrent fever because of impairing thermoregulatory center. This study introduced disability score to measure outcome and its distribution is shown below in Table 3 . The nonparametric Spearman rank correlation coefficient was used for correlation analysis. A strong correlation was respectively observed between motor and speech function (ρ = 0.856, p = 0.000095), motor and cognitive function (ρ = 0.830, p = 0.000238),speech and cognitive function (ρ = 0.847, p = 0.000130). Table 3 Distribution of disability score in 14 patients with GA1 by motor, cognitive function and speech. Disability Score 3(n = 3) 4(n = 3) 5(n = 2) 6(n = 1) 7(n = 1) 8(n = 3) 9(n = 1) Motor disability Mild(n = 4) 3 1 Moderate(n = 5) 2 2 1 Severe(n = 5) 4 1 Speech Flunt/nearly fluent(n = 5) 3 2 Single words(n = 4) 1 2 1 absence(n = 5) 4 1 Cognitive function normal(n = 8) 3 3 2 Ambiguous(n = 5) 1 4 Not normal(n = 1) 1 Comparing the NBS group and non-NBS group, there were statistical significance differences in disability score(p = 0.004), motor function(p = 0.024) and speech function (p = 0.008), but no statistical significance differences in cognitive function (p = 0.106).(Table 4 ) Table 4 Scores of motor, cognition and speech from NBS group and non-NBS group Patients NO. Motor Speech Cognitive Disability Score N1 - - - - N2 1 1 1 3 N3 1 1 1 3 N4 2 1 1 4 N5 1 1 1 3 N6 - - - - C1 2 2 1 5 C2 3 3 3 9 C3 2 1 1 4 C4 3 3 2 8 C5 1 2 1 4 C6 2 2 2 6 C7 3 3 2 8 C8 3 3 2 8 C9 3 3 2 8 C10 2 2 1 5 P 0.024 0.008 0.106 0.004 Discussion In this study, we focused on 16 individuals with GA1 at the Third Affiliated Hospital of Zhengzhou University, where receives blood spots samples from the whole province. We summarized findings about clinical, biochemical and molecular features in these patients and followed up their outcomes. The morbidity of GA1 in Henan population is 1 / 172 483, which is closed to the result of a multi-center study 1/185,971 in mainland China, but was obviously lower than 1/ 47,044 in Quanzhou, and 1/64708 in Zhejiang, and 1/89 533 in Jiangsu of southern China, and 1/73 076 in Xi’an, a northern city of China[ 5 , 16 – 19 ].This difference may be due to geographical distribution. In our study, all GA1 patients presented elevated C5DC values, ranging from 0.34 to 5.79 µmol/L (reference value: 0.01–0.27 µmol/L). Our finding is similar to some other study. A study found that 18 GA1 patients in Egypt had elevated C5DC values ranging from 0.44 to 11.2µmol/L[ 20 ]. Another study reported approximately 90% of GA1 patients had increased C5DC values, ranging values from 0.30 to 3.69 µmol/L[ 13 ]. Up to now, more than 250 mutations have been described in the Human Gene Mutation Database. In our study, we identified 20 variants in 28 independent alleles and all of them were compound heterozygous mutations. We found 4 novel variants:c.523G > A (p.G175S), c.1297G > C (p.A433P), c.467G > A (p.G156D) and c.1125T > G (p.C375W). There are no descriptions in the available databases. In silico analyses, the 4 novel variants were predicted to be damaging and disease-causing. In our study, the most prevalent mutation was c.1064G > A (p.R355H), of which the allelic frequency was 17.86% (5/28). A previous study reported that p.R355H had a frequency of 8.8% (3/34 alleles)[ 21 ] and a recent research reported c.1064G > A (p.R355H) as the second frequent variant(7.4%) in mainland China[ 13 ]. This information may indicates a high frequency of R355H in Asian population. In addition, p.R355H was reported enzyme deficiency in cultured fibroblasts and no expression in E. coli[ 22 ]. In European population, p.Arg402Trp was predicted to be the most frequent variant[ 23 ]. The remaining mutations identified by our study presented heterogeneous and were widely mapped throughout the whole gene. The clinical features and severity of GA1 patients presented marked heterogeneity and neurological damage varied widely. Some patients presents asymptomatic while some other patients presented severe developmental delay during neonatal period and typically suffered from acute encephalopathy crisis before the age of 3 years[ 24 ]. In our cohort, the symptomatic patients had a onset age ranging from 0 to 12 months, of whom two patients already had abnormal MRI or ultrasound manifestations during fetal period. 78.6%(11/14) patients experienced metabolic encephalopathy, of whom 4 patients were acute onset inducing by fever, vaccination and injury, while another 7 patients showed encephalopathy crisis with no obvious inducement. This result is consistent with a previous report by Boy, N. However, only 21.4% (3/14) patients presented typical macrocephaly, that was far below the value reported in other research[ 14 , 25 ]. The research acquired 13 patients’ brain MRI data. 11patients( 84.6%) displayed abnormal and 2 patients (15.4%)displayed normal. The mainly abnormal findings were cerebral dysplasia (5/11, 45.5%), arachnid/ependymal cysts (5/11, 45.5%), following by basal ganglia abnormal sign (2/11, 18.2%), subdural effusion (1/11, 9.1%), hydrocephaly (1/11, 9.1%) and abnormal bilateral white matter (1/11, 9.1%). In our study, the most common abnormal brain MRI findings were cerebral dysplasia and arachnid/ependymal cysts (both 45.5%,5/11). Among the five patients with cerebral dysplasia, three presented severe motor and speech disability but moderate cognitive function, while two patients showed mild or moderate disability in all three respects. Two patients presented basal ganglia abnormal sign. One patient for each showed abnormal bilateral white matter, subdural effusion and hydrocephaly. It is worth mentioning that the two patients with basal ganglia abnormal sign presented most severe developmental disability, while the patients with cysts showed mild or moderate disability. Previous research described that in patients with basal ganglia abnormal sign, more than half experienced seizures, but this has not happened in our patients. Meanwhile, almost 40% of these patients had movement disorders and poor outcome, the same situation happened to our two patients, who were both unable to stand or walk[ 14 ]. In our study, a strong correlation was respectively discovered between motor, speech and cognitive function. This finding was different from a previous study that showed strong correlation between motor function and speech, a slight correlation between speech and cognitive function but no correlation between motor and cognitive function[ 15 ]. We also compared disability score between NBS group and non-NBS group. There are statistical significance differences in motor and speech function, but no statistical significance differences in cognitive function. Patients diagnosed by newborn screening have better outcome. On the contrary, clinical patients had a high frequency of developmental disability and poor outcome. The two siblings from the same family presented different clinical outcomes. The little sister has normal developments that benefit from newborn screening. The elder sister presents developmental retardation because of delayed treatment. Therefore, NBS is a beneficial intervention for early GA1 diagnosis, and is vital for better outcome and preventing from neurological damage. As far as we know, GA1 has been entrancing to the NBS program in majority provinces of China. For Henan province, our center started the program since 2013 and 1 034 896 newborns had already been screened. However, the overall screening rate is only 10% of births. In our cohort, one patient received screening at neonatal period but his blood sample was sent to an illegal medical laboratory not our center. Unfortunately, because of lacking metabolic disease specialist, the doctor on basic hospital was unable to make the right diagnosis. Until the age of 9 months, he was transferred to our hospital and was diagnosed with GA1. Delayed treatment resulted in severe disability of this patient. This case strongly suggests that standardized with professional management of NBS is essential and government policies are urgently needed. At the same time, there are some limitations in this research. Firstly, of 6 patients diagnosed by newborn screening, only one received screening at 72 hours after birth, the others ranged from 5 days to 25 days, which may due to long or delayed delivery. Early diagnosis is delayed to some extent. Quality control should be strengthened before experiment. Secondly, mutations identified by our study presented heterogeneous and limited amount. We are unable to observe definite correlation between genotype and phenotype. But we are looking forward to further research about this in the future. Conclusions In general, diagnosis and treatment management of GA1 are still in the initial stage in Henan. There is a lack of comprehensive understanding of this disease. Our study investigated 16 GA1 patients in Henan province of China. We focused on the clinical, biochemical, and molecular characterizations, providing comprehensive information. The incidence of GA1 in Henan population was predicted to be 1 in 172483 newborns. The c.1064G > A (p.R355H) variant was the most prevalent GCDH variant in Henan population. We identified four novel mutations in the GCDH gene, and they expand the mutational spectrum of GA-1. Clinical outcome varied from asymptomatic to severe disability. Our results showed a significant difference between NBS patients and clinical patients and the former had better outcome. Professional management of NBS programs and experienced genetic metabolic disease experts will be very important and urgent. Methods Patients We focused on sixteen patients (nine females and seven males) with GA1 at the Third Affiliated Hospital of Zhengzhou University from January 2013 to December 2021. Six (four females and two males) of them were identified by newborn screening, whereas ten patients were admitted to screen because of suspected clinical symptoms. Two patients were siblings (patient N2 and C1). The age of these patients ranged from 15 months to 14 years. Informed consent was signed by the parents of GA1 patients and this research was approved by the Ethics Committee of The Third Affiliated Hospital of Zhengzhou University.(2019-67) Biochemical Analysis Dried blood spots on 903 filter paper ( Wallac Oy,Turku,Finland) were collected from all infants or suspected patients. Liquid chromatography-tandem mass spectrometer (LC-MS/MS) technology was used to detect the level of glutarylcarnitine (C5DC) and the C5DC/capryloylcarnitine (C8) rate of samples by tandem mass spectrometer (API 4000, American BioSystems, USA). Gas chromatography-mass spectrometry (GCMS-QP2010, Shimadzu, Japan) was used to quantify the glutaric acid (GA) and 3 hydroxyglutaric acid(3-OH-GA) in urine from suspected patients. Gene Mutations Analysis The genomic DNA of positive patients and their parents was isolated from peripheral blood leukocytes. The GCDH mutations of patients were detected by the next-generation sequencing panel, and parental mutations were verified by Sanger sequencing. Mutations were checked using the available databases HGMD ( https://www.hgmd.cf.ac.uk ), ClinVar ( https://www.ncbi.nlm.nih.gov/clinvar)an d dbSNP ( http://www.ncbi.nlm.nih.gov/SNP/ ). PolyPhen2( http://genetics.bwh.harvard.edu/pph2/ ), SIFT(Sorting Intolerant From Tolerant), REVEL (rare exome variant ensemble learner) and MutationTaster were used to predict the potential pathogenic effects of these variants. Disease Diagnosis Individuals with high levels of C5DC and the C5DC/C8 ratio in the dried blood spots detected by LC-MS/MS were regarded as suspect patients. They were recalled to have second test. Rising level of C5DC in blood and increased excretion of GA and 3-OH-GA in urine combined with typical clinical features, general laboratory examinations provided strong evidences for the disease diagnosis. Patients were finally confirmed with GA1 by GCDH gene mutations analysis. Treatment And Outcome In consideration of early diagnosis and intervention for positive individuals, we adopted measures to diagnosis and treatment in the meantime. The treatment strategy included a restrict protein diet with special lysine /tryptophan-free formula before six years old and age-appropriate limited protein intake diet after six years of age. L-carnitine (50–100 mg/kg/day)was supplemented everyday. Meanwhile, riboflavin (20–200 mg/day) and emergency treatment were given if necessary[ 2 ]. Clinical data were collected through medical record and follow up. Using motor, cognition and speech score to evaluate clinical outcome. Motor disability was scored as 1 when no or mild motor dysfunction, as 2 when moderate motor dysfunction, and as 3 when severe disability that need wheelchair to assist or completely unable to move. Cognitive function was scored as 1 when normal or almost normal, as 2 when in the middle and as 3 when not normal or IQ was below 70. Speech function was scored as 1 when fluent or proximity fluent, as 2 when only with single words, and as 3 when speech absence. Sum up the scores from motor, cognition and speech as disability score to evaluate clinical outcome[ 15 ]. Statistical analysis Statistical analysis was executed with SPSS.21 (IBM, USA). The nonparametric Spearman rank correlation coefficient was used for correlation analysis. Mann-Whitney U test was used to compare outcomes between NBS group and non-NBS group. Statistical significance was identified when p < 0.05. Abbreviations GA1: Glutaric acidemia type 1 GCDH: glutaryl-CoA dehydrogenase C5DC: glutarylcarnitine 3-OH-GA: 3-hydroxyglutaric acid HGMD: Human Gene Mutation Database C8: capryloylcarnitine LC-MS/MS: Liquid chromatography-tandem mass spectrometer NGS: Next-generation sequencing SIFT: Sorting Intolerant From Tolerant REVEL: rare exome variant ensemble learner NBS: newborn screening Declarations Availability of data and materials The datasets used and/or analysed during the current study can be acquired from the corresponding author upon a reasonable request. Acknowledgements We thank all the patients and their families for their participation.We thank all the laboratory and clinical staffs for their contributions to this study. Author contributions Xinyun Zhu performed the study design, data analysis, literature search and manuscript preparation. Xiaole Li, Yizhuo Xu and Linfei Li assisted with data collection, Suna Liu and Liting Jia assisted with revising the manuscript, Min Ni carried out LC/MS and GC/MS tests. Yaqing Guo performed the genetic tests and variants analysis. Dehua Zhao designed and supervised the research. All authors read and approved the final manuscript. Funding This work was funded by the Science and Technology Research Project of Henan Province [grant number SBGJ 202102182]; the Key R & D and Promotion Special Project of Henan Province [2121102310733];Medical Science and Technology Joint construction Project of Henan Province [LHGJ20190357];Medical Science and Technology Joint construction Project of Henan Province [LHGJ20200461];Medical Science and Technology Joint construction Project of Henan Province [LHGJ20200644];Medical Science and Technology Joint construction Project of Henan Province [LHGJ20210443] Ethics approval and consent to participate This study was approved by the Ethical Committee of Ethics Committee of The Third Affiliated Hospital of Zhengzhou University. Written informed consent was obtained from the parents of all patients for collection of DBS samples and publication of medical data. Consent for publication Consent was obtained from the parents of all patients for publication. Competing interests The authors declare that they have no competing interests. References Kolker S, Garbade SF, Greenberg CR, Leonard JV, Saudubray JM, Ribes A, et al. Natural history, outcome, and treatment efficacy in children and adults with glutaryl-CoA dehydrogenase deficiency. Pediatr Res. 2006; 59(6):840-7. Boy N, Muhlhausen C, Maier EM, Heringer J, Assmann B, Burgard P, et al. Proposed recommendations for diagnosing and managing individuals with glutaric aciduria type I: second revision. J Inherit Metab Dis. 2017; 40(1):75-101. Lin Y, Zheng Q, Zheng T, Zheng Z, Lin W, Fu Q. Expanded newborn screening for inherited metabolic disorders and genetic characteristics in a southern Chinese population. Clin Chim Acta. 2019; 494:106-11. Yang C, Zhou C, Xu P, Jin X, Liu W, Wang W, et al. Newborn screening and diagnosis of inborn errors of metabolism: A 5-year study in an eastern Chinese population. Clin Chim Acta. 2020; 502:133-8. Lin Y, Wang W, Lin C, Zheng Z, Fu Q, Peng W, et al. Biochemical and molecular features of Chinese patients with glutaric acidemia type 1 detected through newborn screening. Orphanet J Rare Dis. 2021; 16(1):339. Heringer J, Boy SP, Ensenauer R, Assmann B, Zschocke J, Harting I, et al. Use of guidelines improves the neurological outcome in glutaric aciduria type I. Ann Neurol. 2010; 68(5):743-52. Strauss KA, Puffenberger EG, Robinson DL, Morton DH. Type I glutaric aciduria, part 1: natural history of 77 patients. Am J Med Genet C Semin Med Genet. 2003; 121C(1):38-52. Pfeil J, Listl S, Hoffmann GF, Kolker S, Lindner M, Burgard P. Newborn screening by tandem mass spectrometry for glutaric aciduria type 1: a cost-effectiveness analysis. Orphanet J Rare Dis. 2013; 8:167. Govender R, Mitha A, Mubaiwa L. A review of patients with glutaric aciduria type 1 at Inkosi Albert Luthuli Central Hospital, Durban, South Africa. S Afr Med J. 2017; 107(3):201-4. Boy N, Mengler K, Thimm E, Schiergens KA, Marquardt T, Weinhold N, et al. Newborn screening: A disease-changing intervention for glutaric aciduria type 1. Ann Neurol. 2018; 83(5):970-9. Goodman SI, Markey SP, Moe PG, Miles BS, Teng CC. Glutaric aciduria; a "new" disorder of amino acid metabolism. Biochem Med. 1975; 12(1):12-21. Zayed H, El Khayat H, Tomoum H, Khalifa O, Siddiq E, Mohammad SA, et al. Clinical, biochemical, neuroradiological and molecular characterization of Egyptian patients with glutaric acidemia type 1. Metab Brain Dis. 2019; 34(4):1231-41. Gurbuz BB, Yilmaz DY, Coskun T, Tokatli A, Dursun A, Sivri HS. Glutaric aciduria type 1: Genetic and phenotypic spectrum in 53 patients. Eur J Med Genet. 2020; 63(11):104032. E H, Liang L, Zhang H, Qiu W, Ye J, Xu F, et al. Evaluation of the Clinical, Biochemical, Neurological, and Genetic Presentations of Glutaric Aciduria Type 1 in Patients From China. Front Genet. 2021; 12:702374. Kyllerman M, Skjeldal O, Christensen E, Hagberg G, Holme E, Lonnquist T, et al. Long-term follow-up, neurological outcome and survival rate in 28 Nordic patients with glutaric aciduria type 1. Eur J Paediatr Neurol. 2004; 8(3):121-9. Shi XT, Cai J, Wang YY, Tu WJ, Wang WP, Gong LM, et al. Newborn screening for inborn errors of metabolism in mainland china: 30 years of experience. JIMD Rep. 2012; 6:79-83. Yang L, Yin H, Yang R, Huang X. Diagnosis, treatment and outcome of glutaric aciduria type I in Zhejiang Province, China. Med Sci Monit. 2011; 17(7):PH55-9. Yang Y, Wang L, Wang B, Liu S, Yu B, Wang T. Application of Next-Generation Sequencing Following Tandem Mass Spectrometry to Expand Newborn Screening for Inborn Errors of Metabolism: A Multicenter Study. Front Genet. 2019; 10:86. Zhang R, Qiang R, Song C, Ma X, Zhang Y, Li F, et al. Spectrum analysis of inborn errors of metabolism for expanded newborn screening in a northwestern Chinese population. Sci Rep. 2021; 11(1):2699. Mosaeilhy A, Mohamed MM, C GPD, El Abd HSA, Gamal R, Zaki OK, et al. Genotype-phenotype correlation in 18 Egyptian patients with glutaric acidemia type I. Metab Brain Dis. 2017; 32(5):1417-26. Mushimoto Y, Fukuda S, Hasegawa Y, Kobayashi H, Purevsuren J, Li H, et al. Clinical and molecular investigation of 19 Japanese cases of glutaric acidemia type 1. Mol Genet Metab. 2011; 102(3):343-8. Christensen E, Ribes A, Merinero B, Zschocke J. Correlation of genotype and phenotype in glutaryl-CoA dehydrogenase deficiency. J Inherit Metab Dis. 2004; 27(6):861-8. Pokora P, Jezela-Stanek A, Rozdzynska-Swiatkowska A, Jurkiewicz E, Bogdanska A, Szymanska E, et al. Mild phenotype of glutaric aciduria type 1 in polish patients - novel data from a group of 13 cases. Metab Brain Dis. 2019; 34(2):641-9. Boy N, Heringer J, Brackmann R, Bodamer O, Seitz A, Kolker S, et al. Extrastriatal changes in patients with late-onset glutaric aciduria type I highlight the risk of long-term neurotoxicity. Orphanet J Rare Dis. 2017; 12(1):77. Renaud DL. Leukoencephalopathies associated with macrocephaly. Semin Neurol. 2012; 32(1):34-41. Cite Share Download PDF Status: Posted Version 1 posted 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-1274419","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":88893146,"identity":"7e4b1d0a-53e1-433e-b7bd-37eed945519d","order_by":0,"name":"Xinyun Zhu","email":"","orcid":"https://orcid.org/0000-0003-3743-4403","institution":"Zhengzhou University Third Hospital and Henan Province Women and Children's Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xinyun","middleName":"","lastName":"Zhu","suffix":""},{"id":88893147,"identity":"1148f34d-4fb5-46a6-8128-11df93fe241e","order_by":1,"name":"Xiaole Li","email":"","orcid":"","institution":"Zhengzhou University Third Hospital and Henan Province Women and Children's Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Xiaole","middleName":"","lastName":"Li","suffix":""},{"id":88893148,"identity":"d3469c99-ba8a-467d-addc-a125e20a8457","order_by":2,"name":"Suna Liu","email":"","orcid":"","institution":"Zhengzhou University Third Hospital and Henan Province Women and Children's Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Suna","middleName":"","lastName":"Liu","suffix":""},{"id":88893149,"identity":"60d08792-ab52-46f5-b221-c11ab825ca5e","order_by":3,"name":"Min Ni","email":"","orcid":"","institution":"Zhengzhou University Third Hospital and Henan Province Women and Children's Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Min","middleName":"","lastName":"Ni","suffix":""},{"id":88893150,"identity":"33597c76-8743-408c-a8b3-5b809b3581bc","order_by":4,"name":"Yaqing Guo","email":"","orcid":"","institution":"Zhengzhou University Third Hospital and Henan Province Women and Children's Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yaqing","middleName":"","lastName":"Guo","suffix":""},{"id":88893151,"identity":"23c2323a-cec6-4a49-895b-c4ca03d683c6","order_by":5,"name":"Yizhuo Xu","email":"","orcid":"","institution":"Zhengzhou University Third Hospital and Henan Province Women and Children's Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Yizhuo","middleName":"","lastName":"Xu","suffix":""},{"id":88893152,"identity":"8ca3a1c6-2ddd-4b41-aabb-dcca2ecb2da2","order_by":6,"name":"Liting Jia","email":"","orcid":"","institution":"Zhengzhou University Third Hospital and Henan Province Women and Children's Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Liting","middleName":"","lastName":"Jia","suffix":""},{"id":88893153,"identity":"42d3b3af-6b1d-4c88-b01c-33a3585f4ba0","order_by":7,"name":"Linfei Li","email":"","orcid":"","institution":"Zhengzhou Children's Hospital","correspondingAuthor":false,"submittingAuthor":false,"prefix":"","firstName":"Linfei","middleName":"","lastName":"Li","suffix":""},{"id":88893154,"identity":"293415a4-cc94-4803-8767-1d962ddba15c","order_by":8,"name":"Dehua Zhao","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA6klEQVRIiWNgGAWjYDACCSDmYTjAwMDffPDBBwMbOxK0SBxLNpxRkJZMghaGHDVpng+HGBsI6ZCf3fzwwZuKO4n9DWfYpG0MDjAzsB8+ugGfFsY5x4wN55x5ljjjcO9h6xyDO3wMPGlpN/BpYZZIMJPmbTuc2HDgXOLtHINnzAwSPGZ4tbBJpH+T5v13OHH+gRwDaQuDw4wNhLTwSOQAbWk4nLjhQI6RNAMxWiQkcooN5xw7bLzxBjCQewzSktkI+UV+RvrGB29qDsvOOw+Myh9/bOz42Q8fw6sFi+9IUz4KRsEoGAWjABsAAITlUgv48GDQAAAAAElFTkSuQmCC","orcid":"https://orcid.org/0000-0002-2836-7264","institution":"Zhengzhou University Third Hospital and Henan Province Women and Children's Hospital","correspondingAuthor":true,"submittingAuthor":false,"prefix":"","firstName":"Dehua","middleName":"","lastName":"Zhao","suffix":""}],"badges":[],"createdAt":"2022-01-19 02:59:02","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-1274419/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-1274419/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":19051912,"identity":"41af7b40-e728-4971-90eb-5be41f50b9c7","added_by":"auto","created_at":"2022-03-09 20:27:40","extension":"jpg","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":449693,"visible":true,"origin":"","legend":"\u003cp\u003eLegend not included with this version.\u003c/p\u003e","description":"","filename":"figure.jpg","url":"https://assets-eu.researchsquare.com/files/rs-1274419/v1/b9d3b430b32643e47e42ac5f.jpg"},{"id":21451034,"identity":"82c296b4-ef02-46f7-8c34-e1218d9ea17a","added_by":"auto","created_at":"2022-05-13 19:37:58","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":570886,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-1274419/v1/027943b0-29cf-49dd-8a9d-87ca7b204498.pdf"}],"financialInterests":"","formattedTitle":"\u003cp\u003eClinical, Biochemical and Molecular Characterizations of Patients With Glutaric Aciduria Type 1 in Henan Province, China\u003c/p\u003e","fulltext":[{"header":"Background","content":"\u003cp\u003eGlutaric aciduria type 1 (GA1, OMIM#231670) is a rare autosomal recessive metabolism disorder that caused by glutaryl-CoA dehydrogenase (GCDH) deficiency. This enzyme activity is remarkable decreased because of variants in encoding GCDH gene which locates on chromosome 19p13.2. in the metabolism process of lysine, hydroxylysine, and tryptophan, the ability which transforms glutaryl-CoA to crotonylCoA is decreased. Thus leading to an abnormal accumulation of glutarylcarnitine (C5DC),glutaric acid (GA) and 3-hydroxyglutaric acid (3-OH-GA) in a variety of body tissues, especially in brain[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Estimated worldwide prevalence of GA1 is 1 in 110,000 newborns[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e].In China, the nationwide incidence of GA1 is between 1/171,411 and 1/52,078[\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e, \u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. It has been reported that the incidence of GA1 in Quanzhou, a south region of China, was 1 in 47,044 newborns[\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. The clinical features and severity of GA1 patients were significantly different. Some patients are asymptomatic whereas some appear neurological symptoms such as dystonia, dyskinesia, hypotonia and motor disability. The clinical features mainly include macrocephaly, developmental regression, acute encephalopathy, which is often triggered by fever, infection, vaccination or surgery, accompanying by seizures, cerebral dysplasia ,subdural effusion and cyst[\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e, \u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e]. Treatment strategy of GA1 includes restricted protein with low lysine/tryptophan diet, L-carnitine and emergency treatment[\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. Because of lacking typical features before acute encephalopathic crisis or latent onset, early diagnosis becomes difficult. Early diagnosis and treatment can effectively reduce the occurrence of encephalopathic crises[\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e, \u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Biochemical changes including increased C5DC, glutaric acid (GA) and 3-hydroxyglutaric acid3-OH-GA) can be detected by tandem mass spectrometer and gas chromatography-mass spectrometry.GA1 has been brought into a variety of national newborn screening (NBS) panels[\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e]. Early diagnosis through NBS is vital to achieve a better outcome[\u003cspan citationid=\"CR9\" class=\"CitationRef\"\u003e9\u003c/span\u003e, \u003cspan citationid=\"CR10\" class=\"CitationRef\"\u003e10\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eSince first reported in 1975[\u003cspan citationid=\"CR11\" class=\"CitationRef\"\u003e11\u003c/span\u003e], more than 250 mutations have been described in the Human Gene Mutation Database (HGMD:\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e\u003ca href=\"http://www.hgmd.cf.ac.uk\" target=\"_blank\"\u003ewww.hgmd.cf.ac.uk\u003c/a\u003e\u003c/span\u003e\u003c/span\u003e). Some common variants have been identified, including c.*165A\u0026thinsp;\u0026gt;\u0026thinsp;G in Egyptian patients[\u003cspan citationid=\"CR12\" class=\"CitationRef\"\u003e12\u003c/span\u003e]p. Leu340Phe in Turkish patients[\u003cspan citationid=\"CR13\" class=\"CitationRef\"\u003e13\u003c/span\u003e] c.1244-2A\u0026thinsp;\u0026gt;\u0026thinsp;C in Chinese patients[\u003cspan citationid=\"CR14\" class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eIn Henan, a middle region of China, newborn screening for GA1 has been performed since 2013. However, there are rare reports focusing on GA1 in Henan province. Data about the prevalence, NBS experience, variant spectrum and clinical manifestations in Henan are unclear. In this research, we investigated the clinical, biochemical, molecular characterizations and outcome of 16 GA1 patients in Henan province. This research aims to improve our further understanding characteristics about GA1 in Henan province.\u003c/p\u003e"},{"header":"Results","content":"\u003cdiv class=\"Section2\" id=\"Sec3\"\u003e\n \u003ch2\u003e1.incidence of GA1 in Henan\u003c/h2\u003e\n \u003cp\u003eDuring January 2013 to December 2021,1 034 896 newborns received screening at the Third Affiliated Hospital of Zhengzhou University and 6 newborns were confirmed with GA1. The incidence of GA1 in Henan population was 1 in 172 483 newborns.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec4\"\u003e\n \u003ch2\u003e2.Biochemical features\u003c/h2\u003e\n \u003cp\u003eThe screening results of all patients showed increased C5DC level that ranged from 0.34 to 5.79 \u0026micro;mol/L (reference value: 0.01\u0026ndash;0.27 \u0026micro;mol/L). The mean C5DC value were 1.91\u0026thinsp;\u0026plusmn;\u0026thinsp;1.66 \u0026micro;mol/L. Urine GC/MS analysis showed elevated excretions of GA and 3-OH-GA in all patients.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec5\"\u003e\n \u003ch2\u003e3.Molecular genetics analysis\u003c/h2\u003e\n \u003cp\u003eMolecular genetics analysis was available in 14 patients. Twenty mutations were discovered in the 14 patients, including 18 missense mutations, a splicing mutation and a frameshift deletion (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e1\u003c/span\u003e). All patients had compound heterozygous mutations. The most common mutation was c.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.R355H), of which the allelic frequency was 17.86% (5/28), following by c.1109T\u0026thinsp;\u0026gt;\u0026thinsp;C (p.L370P), c.648G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.S216S), c.395G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.R132Q) and c.938G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.R313Q), and they had the same allelic frequency 7.14% (2/28). Among the twenty mutations, sixteen mutations have been reported previously and four variants were identified as novel by our team, namely c.523G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.G175S), c.1297G\u0026thinsp;\u0026gt;\u0026thinsp;C (p.A433P), c.467G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.G156D) and c.1125T\u0026thinsp;\u0026gt;\u0026thinsp;G (p.C375W). The four novel variants have no descriptions in the available databases. Novel variants of GCDH were shown in Fig.\u0026nbsp;1. However, c.467G\u0026thinsp;\u0026gt;\u0026thinsp;A was located in a highly homologous region and belonged to a special gene structure. Due to the limitation of Sanger detection technology, this locus failed to be verified by Sanger for many times. In silico analyses, the four novel variants had the PolyPhen2 values 1, 0.997, 1 and 1 respectively, suggesting probably damaging. Mutation Taster analyses presented that all the four variants are disease-causing. SIFT and REVEL analyses both showed that all the novel variants are damaging.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab1\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 1\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eBiochemical and molecular features of 16 GA1 patients\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003ePatients NO.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eC5DC(\u0026micro;mol/L)\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\n \u003cp\u003eUrinary GA and 3-OH-GA\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eGenotype\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eType of mutation\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\" colspan=\"2\"\u003e\n \u003cp\u003eREVEL prediction\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAllele 1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAllele 2\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAllele 1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAllele 2\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAllele 1\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAllele 2\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.12\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg355His)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.481C\u0026thinsp;\u0026gt;\u0026thinsp;G(p.Arg161Gly)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.29\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1109T\u0026thinsp;\u0026gt;\u0026thinsp;C(p.Leu370Pro)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.648G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Ser216Ser)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5.79\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.533G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Gly178Glu)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg355His)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.47\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.523G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Gly175Ser)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1297G\u0026thinsp;\u0026gt;\u0026thinsp;C(p.Ala433Pro)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.34\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1242A\u0026thinsp;\u0026gt;\u0026thinsp;C(p.Glu414Asp)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.395G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg132Gln)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3.91\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1109T\u0026thinsp;\u0026gt;\u0026thinsp;C(p.Leu370Pro);\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.648G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Ser216Ser)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.83\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1240G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Glu414Lys)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.938G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg313Gln)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.43\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.937C\u0026thinsp;\u0026gt;\u0026thinsp;T(p.Arg313Trp)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg355His)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2.25\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.395G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg132Gln)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.956\u0026thinsp;+\u0026thinsp;2T\u0026thinsp;\u0026gt;\u0026thinsp;A(p. ?)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003esplicing\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.69\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1240G\u0026thinsp;\u0026gt;\u0026thinsp;T(p.Arg402Trp)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.467G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Gly156Asp)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.92\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.938G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg313Gln);\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1233delC(p.Asp411Kfs*12)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eframeshift deletion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.88\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg355His)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.892G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Ala298Thr)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1.39\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A(p.Arg355His)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1125T\u0026thinsp;\u0026gt;\u0026thinsp;G(p.Cys375Trp)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e0.8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e5.04\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eElevated\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.1204C\u0026thinsp;\u0026gt;\u0026thinsp;T(p.Arg402Trp)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ec.640A\u0026thinsp;\u0026gt;\u0026thinsp;G(p.Thr214Ala)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003emissense\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDamaging\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"9\"\u003e\u003cstrong\u003eC5DC: glutarylcarnitine,GA: glutaric acid, 3HGA: 3-hydroxyglutaric acid,REVEL :rare exome variant ensemble learner,NA: not available.\u003c/strong\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003cp\u003e\u003cbr\u003e\u003c/p\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec6\"\u003e\n \u003ch2\u003e4.Clinical findings\u003c/h2\u003e\n \u003cp\u003eClinical features of 16 patients are summarized below (Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e2\u003c/span\u003e). Two patients were failure to visit. Of the rest 14 patients, 2 patients were asymptomatic and 12 patients were symptomatic. The 12 patients with clinical symptoms had a median age 2.5 months (range: 0\u0026ndash;12 months) at onset of symptoms and a median age 6.5 months at diagnosis (range: 20 days \u0026minus;\u0026thinsp;10 years). Patients N1-N6 were diagnosed through newborn screening. Patients C1-C10, who didn\u0026rsquo;t receive newborn screening, were symptomatic and clinical diagnosed with GA1.\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab2\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 2\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eClinical features of 16 GA1 patients\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePatients NO.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eGender\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCurrent age\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAge at onset\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAge at\u003c/p\u003e\n \u003cp\u003efirst screening\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eAge at\u003c/p\u003e\n \u003cp\u003ediagnosis\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eClinical\u003c/p\u003e\n \u003cp\u003esymptoms\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eTrigger events\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMRI brain findings\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eNote\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e13D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eLoss to follow-up\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4Y2M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e20D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e39D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003enormal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAsymptomatic\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5Y2M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e30D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e25D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e50D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMacrocephaly\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBilateral temporal arachnid cysts, subependymal cysts\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y3M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFetal period\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e34D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDystonia,\u003c/p\u003e\n \u003cp\u003eRetardation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eependymal cyst\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2Y7M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e35D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003enormal\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDied\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e16D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDied\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e14Y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10Y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e10Y1M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eRegression,Limb soft,seizure\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003efever\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCerebral dysplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3Y2M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e27D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eBucking,feeding difficulty,Dystonia,\u003c/p\u003e\n \u003cp\u003eLimb soft\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ebasal ganglia abnormal sign\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4Y1M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e42D\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDystonia,\u003c/p\u003e\n \u003cp\u003eRetardation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNA\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4Y6M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMacrocephaly,\u003c/p\u003e\n \u003cp\u003eseizure,Dystonia, regression\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003evaccination\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSubdural effusion,\u003c/p\u003e\n \u003cp\u003eCerebral dysplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6Y11M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y6M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y7M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eRegression,\u003c/p\u003e\n \u003cp\u003eDystonia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003efever\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003earachnoid cyst,\u003c/p\u003e\n \u003cp\u003eCerebral dysplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3Y11M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y1M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eRegression,\u003c/p\u003e\n \u003cp\u003edysphagia,\u003c/p\u003e\n \u003cp\u003efeeding difficulty\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003einjury\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ecysts, brain effusion\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eF\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8Y2M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6.5M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDystonia, Retardation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003ebasal ganglia abnormal sign\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4Y3M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFetal period\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMacrocephaly,\u003c/p\u003e\n \u003cp\u003eseizure,Dystonia,\u003c/p\u003e\n \u003cp\u003eBucking,Retardation,Metabolic acidosis\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eHydrocephaly,\u003c/p\u003e\n \u003cp\u003eCerebral dysplasia\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5Y10M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y3M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y4M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDystonia,\u003c/p\u003e\n \u003cp\u003eIrritable\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eCerebral dysplasia,\u003c/p\u003e\n \u003cp\u003eDiffuse abnormal signals in bilateral white matter\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eM\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e7Y8M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1Y\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3Y6M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3Y7M\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eDystonia,\u003c/p\u003e\n \u003cp\u003eRetardation\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003earachnoid cyst\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003ctfoot\u003e\n \u003ctr\u003e\n \u003ctd colspan=\"10\"\u003e\u003cstrong\u003eM: male, F: female, NA: not available.\u003c/strong\u003e\u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tfoot\u003e\n \u003c/table\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/div\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec7\"\u003e\n \u003ch2\u003e4.1.Newborn screening group\u003c/h2\u003e\n \u003cp\u003eAmong six NBS patients, N2 and N5 were asymptomatic. N1 refused to accept treatment or follow-up after diagnosis and current status was unknown.\u003c/p\u003e\n \u003cp\u003eN3 had macrocephaly as the main clinical feature. His head circumference was 49cm at the age of 6 months, but movement and intelligence developments were normal. N4 was detected to has ependymal cyst during fetal period and received newborn screening at 72 hours after birth and then she was diagnosed with GA1. She suffered from moderate movement disorder, mild speech disorder but with normal intelligence. N6 showed extremely high level of C5DC(3.91\u0026micro;mol/L, reference value: 0.01\u0026ndash;0.27) in blood and GA (1919 mmol/molcreatinine, reference value:\u0026lt;2.5 ) in urine. Unfortunately, she was dead before the molecular genetics analysis.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec8\"\u003e\n \u003ch2\u003e4.2.Non-Newborn screening group\u003c/h2\u003e\n \u003cp\u003eC1, sibling of N2, presented convulsion and developmental regression because of fever at the age of six months but was misdiagnosed as encephalitis. She was finally diagnosed with GA1 at ten years old, thanking to her little sister\u0026apos;s screening result.\u003c/p\u003e\n \u003cp\u003eC2 presented bucking, feeding difficulty, limb soft and dystonia. At the age of 20 days, his blood sample was sent to an illegal medical laboratory and the result was abnormal. Unfortunately, because of lacking metabolic specialist, the doctor on basic hospital was unable to make the right diagnosis. Until at the age of 9 months, he was transferred to our hospital and was diagnosed with GA1. Besides, he had an older brother who died from encephalopathy crisis.\u003c/p\u003e\n \u003cp\u003eC3 was born at 36 weeks of gestational age and showed dystonia. At 4 months of age, he was referred to our center and diagnosed with GA1.\u003c/p\u003e\n \u003cp\u003eC4,C5 and C6 showed developmental regression because of fever, vaccination or tumble. In addition, C4 presented macrocephaly, seizure, dystonia and C6 presented dysphagia, feeding difficulty at the same time.\u003c/p\u003e\n \u003cp\u003eC7 had dystonia and severe motor disability and was diagnosed with GA1 when she was 6.5 months old.\u003c/p\u003e\n \u003cp\u003eC8 had enlarged head circumference in utero, which was discovered from prenatal ultrasound at 5 months of gestational age. Postnatal clinical manifestations were macrocephaly, seizure, dystonia, bucking, neurodevelopmental lag and metabolic acidosis, but he was failed to screen in time and was treated as hypoxic-ischemic encephalopathy. Until referred to our hospital at 5 months old, he was finally diagnosed with GA1.\u003c/p\u003e\n \u003cp\u003eSimilarly, patients C9 and C 10 showed dystonia, irritable and retardation at on set but were diagnosed accurately till the age of 1.3 years and 3.6 years respectively.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec9\"\u003e\n \u003ch2\u003e5.MRI findings\u003c/h2\u003e\n \u003cp\u003eThe research acquired 13 patients\u0026rsquo; brain MRI data. 11 patients( 84.6%) displayed abnormal and 2 patients (15.4%)displayed normal .The mainly abnormal findings were cerebral dysplasia (5/11, 45.5%), arachnid/ependymal cysts (5/11, 45.5%), following by basal ganglia abnormal sign (2/11, 18.2%), subdural effusion (1/11, 9.1%), hydrocephaly (1/11, 9.1%) and abnormal bilateral white matter (1/11, 9.1%).\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv class=\"Section2\" id=\"Sec10\"\u003e\n \u003ch2\u003e6.Follow-up and outcome\u003c/h2\u003e\n \u003cp\u003eAll patients got appropriate treatment immediately. As for the available 14 patients, we make regular follow-up visit until December 2021. Current age of these patients ranges from 15 months to 14 years (median age: 53 months).\u003c/p\u003e\n \u003cp\u003eFour patients diagnosed by NBS have basically normal developments. N2 and N5 have normal development and already attended the kindergarten. N3 also has normal developments and the macrocephaly has been improved. N4 present normal speech and intelligence development but moderate motor disability.\u003c/p\u003e\n \u003cp\u003eFour clinical patients(C1,C3,C5,C10)who were diagnosed by expanded screening, got notable improvements after treatment and three of them(C3,C5,C10) are able to attend the kindergarten or primary school. As for C1, intelligence function trends to normal but she remains moderate motor and speech retardation. On the contrary, six patients(C2,C4,C6-C9) received recommended treatment immediately after diagnosis but got no significant improvement and keep severe brain retardation. They are still unable to walk, speech or move. In addition, patient C8 suffers from hydrocephaly and recurrent fever because of impairing thermoregulatory center.\u003c/p\u003e\n \u003cp\u003eThis study introduced disability score to measure outcome and its distribution is shown below in Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e3\u003c/span\u003e. The nonparametric Spearman rank correlation coefficient was used for correlation analysis. A strong correlation was respectively observed between motor and speech function (\u0026rho;\u0026thinsp;=\u0026thinsp;0.856, p\u0026thinsp;=\u0026thinsp;0.000095), motor and cognitive function (\u0026rho;\u0026thinsp;=\u0026thinsp;0.830, p\u0026thinsp;=\u0026thinsp;0.000238),speech and cognitive function (\u0026rho;\u0026thinsp;=\u0026thinsp;0.847, p\u0026thinsp;=\u0026thinsp;0.000130).\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab3\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 3\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eDistribution of disability score in 14 patients with GA1 by motor, cognitive function and speech.\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\" rowspan=\"2\"\u003e\u0026nbsp;\u003c/th\u003e\n \u003cth align=\"left\" colspan=\"7\"\u003e\n \u003cp\u003eDisability Score\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e3(n\u0026thinsp;=\u0026thinsp;3)\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e4(n\u0026thinsp;=\u0026thinsp;3)\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e5(n\u0026thinsp;=\u0026thinsp;2)\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e6(n\u0026thinsp;=\u0026thinsp;1)\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e7(n\u0026thinsp;=\u0026thinsp;1)\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e8(n\u0026thinsp;=\u0026thinsp;3)\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003e9(n\u0026thinsp;=\u0026thinsp;1)\u003c/strong\u003e\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eMotor disability\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eMild(n\u0026thinsp;=\u0026thinsp;4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eModerate(n\u0026thinsp;=\u0026thinsp;5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSevere(n\u0026thinsp;=\u0026thinsp;5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eSpeech\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eFlunt/nearly fluent(n\u0026thinsp;=\u0026thinsp;5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eSingle words(n\u0026thinsp;=\u0026thinsp;4)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eabsence(n\u0026thinsp;=\u0026thinsp;5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cstrong\u003eCognitive function\u003c/strong\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003enormal(n\u0026thinsp;=\u0026thinsp;8)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eAmbiguous(n\u0026thinsp;=\u0026thinsp;5)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eNot normal(n\u0026thinsp;=\u0026thinsp;1)\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"left\"\u003e\u0026nbsp;\u003c/td\u003e\n \u003ctd align=\"char\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003cp\u003e\u0026nbsp;\u003c/p\u003e\n \u003c/div\u003e\n \u003cp\u003eComparing the NBS group and non-NBS group, there were statistical significance differences in disability score(p\u0026thinsp;=\u0026thinsp;0.004), motor function(p\u0026thinsp;=\u0026thinsp;0.024) and speech function (p\u0026thinsp;=\u0026thinsp;0.008), but no statistical significance differences in cognitive function (p\u0026thinsp;=\u0026thinsp;0.106).(Table\u0026nbsp;\u003cspan class=\"InternalRef\"\u003e4\u003c/span\u003e)\u003c/p\u003e\n \u003cdiv class=\"gridtable\"\u003e\n \u003ctable border=\"1\" id=\"Tab4\"\u003e\n \u003ccaption\u003e\n \u003cdiv class=\"CaptionNumber\"\u003eTable 4\u003c/div\u003e\n \u003cdiv class=\"CaptionContent\"\u003e\n \u003cp\u003eScores of motor, cognition and speech from NBS group and non-NBS group\u003c/p\u003e\n \u003c/div\u003e\n \u003c/caption\u003e\n \u003cthead\u003e\n \u003ctr\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003ePatients NO.\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eMotor\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eSpeech\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eCognitive\u003c/p\u003e\n \u003c/th\u003e\n \u003cth align=\"left\"\u003e\n \u003cp\u003eDisability Score\u003c/p\u003e\n \u003c/th\u003e\n \u003c/tr\u003e\n \u003c/thead\u003e\n \u003ctbody\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eN6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e-\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e9\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC4\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC5\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e4\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC6\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e6\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC7\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC8\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC9\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e3\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e8\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003eC10\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e2\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e1\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e5\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003ctr\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e\u003cem\u003eP\u003c/em\u003e\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.024\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.008\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.106\u003c/p\u003e\n \u003c/td\u003e\n \u003ctd align=\"left\"\u003e\n \u003cp\u003e0.004\u003c/p\u003e\n \u003c/td\u003e\n \u003c/tr\u003e\n \u003c/tbody\u003e\n \u003c/table\u003e\n \u003c/div\u003e\n\u003c/div\u003e"},{"header":"Discussion","content":"\u003cp\u003eIn this study, we focused on 16 individuals with GA1 at the Third Affiliated Hospital of Zhengzhou University, where receives blood spots samples from the whole province. We summarized findings about clinical, biochemical and molecular features in these patients and followed up their outcomes. The morbidity of GA1 in Henan population is 1 / 172 483, which is closed to the result of a multi-center study 1/185,971 in mainland China, but was obviously lower than 1/ 47,044 in Quanzhou, and 1/64708 in Zhejiang, and 1/89 533 in Jiangsu of southern China, and 1/73 076 in Xi\u0026rsquo;an, a northern city of China[\u003cspan class=\"CitationRef\"\u003e5\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e16\u003c/span\u003e\u0026ndash;\u003cspan class=\"CitationRef\"\u003e19\u003c/span\u003e].This difference may be due to geographical distribution.\u003c/p\u003e\n\u003cp\u003eIn our study, all GA1 patients presented elevated C5DC values, ranging from 0.34 to 5.79 \u0026micro;mol/L (reference value: 0.01\u0026ndash;0.27 \u0026micro;mol/L). Our finding is similar to some other study. A study found that 18 GA1 patients in Egypt had elevated C5DC values ranging from 0.44 to 11.2\u0026micro;mol/L[\u003cspan class=\"CitationRef\"\u003e20\u003c/span\u003e]. Another study reported approximately 90% of GA1 patients had increased C5DC values, ranging values from 0.30 to 3.69 \u0026micro;mol/L[\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e].\u003c/p\u003e\n\u003cp\u003eUp to now, more than 250 mutations have been described in the Human Gene Mutation Database. In our study, we identified 20 variants in 28 independent alleles and all of them were compound heterozygous mutations. We found 4 novel variants:c.523G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.G175S), c.1297G\u0026thinsp;\u0026gt;\u0026thinsp;C (p.A433P), c.467G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.G156D) and c.1125T\u0026thinsp;\u0026gt;\u0026thinsp;G (p.C375W). There are no descriptions in the available databases. In silico analyses, the 4 novel variants were predicted to be damaging and disease-causing. In our study, the most prevalent mutation was c.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.R355H), of which the allelic frequency was 17.86% (5/28). A previous study reported that p.R355H had a frequency of 8.8% (3/34 alleles)[\u003cspan class=\"CitationRef\"\u003e21\u003c/span\u003e] and a recent research reported c.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.R355H) as the second frequent variant(7.4%) in mainland China[\u003cspan class=\"CitationRef\"\u003e13\u003c/span\u003e]. This information may indicates a high frequency of R355H in Asian population. In addition, p.R355H was reported enzyme deficiency in cultured fibroblasts and no expression in E. coli[\u003cspan class=\"CitationRef\"\u003e22\u003c/span\u003e]. In European population, p.Arg402Trp was predicted to be the most frequent variant[\u003cspan class=\"CitationRef\"\u003e23\u003c/span\u003e]. The remaining mutations identified by our study presented heterogeneous and were widely mapped throughout the whole gene.\u003c/p\u003e\n\u003cp\u003eThe clinical features and severity of GA1 patients presented marked heterogeneity and neurological damage varied widely. Some patients presents asymptomatic while some other patients presented severe developmental delay during neonatal period and typically suffered from acute encephalopathy crisis before the age of 3 years[\u003cspan class=\"CitationRef\"\u003e24\u003c/span\u003e]. In our cohort, the symptomatic patients had a onset age ranging from 0 to 12 months, of whom two patients already had abnormal MRI or ultrasound manifestations during fetal period. 78.6%(11/14) patients experienced metabolic encephalopathy, of whom 4 patients were acute onset inducing by fever, vaccination and injury, while another 7 patients showed encephalopathy crisis with no obvious inducement. This result is consistent with a previous report by Boy, N. However, only 21.4% (3/14) patients presented typical macrocephaly, that was far below the value reported in other research[\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e, \u003cspan class=\"CitationRef\"\u003e25\u003c/span\u003e].\u003c/p\u003e\n\u003cp\u003eThe research acquired 13 patients\u0026rsquo; brain MRI data. 11patients( 84.6%) displayed abnormal and 2 patients (15.4%)displayed normal. The mainly abnormal findings were cerebral dysplasia (5/11, 45.5%), arachnid/ependymal cysts (5/11, 45.5%), following by basal ganglia abnormal sign (2/11, 18.2%), subdural effusion (1/11, 9.1%), hydrocephaly (1/11, 9.1%) and abnormal bilateral white matter (1/11, 9.1%).\u003c/p\u003e\n\u003cp\u003eIn our study, the most common abnormal brain MRI findings were cerebral dysplasia and arachnid/ependymal cysts (both 45.5%,5/11). Among the five patients with cerebral dysplasia, three presented severe motor and speech disability but moderate cognitive function, while two patients showed mild or moderate disability in all three respects. Two patients presented basal ganglia abnormal sign. One patient for each showed abnormal bilateral white matter, subdural effusion and hydrocephaly. It is worth mentioning that the two patients with basal ganglia abnormal sign presented most severe developmental disability, while the patients with cysts showed mild or moderate disability. Previous research described that in patients with basal ganglia abnormal sign, more than half experienced seizures, but this has not happened in our patients. Meanwhile, almost 40% of these patients had movement disorders and poor outcome, the same situation happened to our two patients, who were both unable to stand or walk[\u003cspan class=\"CitationRef\"\u003e14\u003c/span\u003e].\u003c/p\u003e\n\u003cp\u003eIn our study, a strong correlation was respectively discovered between motor, speech and cognitive function. This finding was different from a previous study that showed strong correlation between motor function and speech, a slight correlation between speech and cognitive function but no correlation between motor and cognitive function[\u003cspan class=\"CitationRef\"\u003e15\u003c/span\u003e]. We also compared disability score between NBS group and non-NBS group. There are statistical significance differences in motor and speech function, but no statistical significance differences in cognitive function. Patients diagnosed by newborn screening have better outcome. On the contrary, clinical patients had a high frequency of developmental disability and poor outcome. The two siblings from the same family presented different clinical outcomes. The little sister has normal developments that benefit from newborn screening. The elder sister presents developmental retardation because of delayed treatment. Therefore, NBS is a beneficial intervention for early GA1 diagnosis, and is vital for better outcome and preventing from neurological damage.\u003c/p\u003e\n\u003cp\u003eAs far as we know, GA1 has been entrancing to the NBS program in majority provinces of China. For Henan province, our center started the program since 2013 and 1 034 896 newborns had already been screened. However, the overall screening rate is only 10% of births. In our cohort, one patient received screening at neonatal period but his blood sample was sent to an illegal medical laboratory not our center. Unfortunately, because of lacking metabolic disease specialist, the doctor on basic hospital was unable to make the right diagnosis. Until the age of 9 months, he was transferred to our hospital and was diagnosed with GA1. Delayed treatment resulted in severe disability of this patient. This case strongly suggests that standardized with professional management of NBS is essential and government policies are urgently needed.\u003c/p\u003e\n\u003cp\u003eAt the same time, there are some limitations in this research. Firstly, of 6 patients diagnosed by newborn screening, only one received screening at 72 hours after birth, the others ranged from 5 days to 25 days, which may due to long or delayed delivery. Early diagnosis is delayed to some extent. Quality control should be strengthened before experiment. Secondly, mutations identified by our study presented heterogeneous and limited amount. We are unable to observe definite correlation between genotype and phenotype. But we are looking forward to further research about this in the future.\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eIn general, diagnosis and treatment management of GA1 are still in the initial stage in Henan. There is a lack of comprehensive understanding of this disease. Our study investigated 16 GA1 patients in Henan province of China. We focused on the clinical, biochemical, and molecular characterizations, providing comprehensive information. The incidence of GA1 in Henan population was predicted to be 1 in 172483 newborns. The c.1064G\u0026thinsp;\u0026gt;\u0026thinsp;A (p.R355H) variant was the most prevalent GCDH variant in Henan population. We identified four novel mutations in the GCDH gene, and they expand the mutational spectrum of GA-1. Clinical outcome varied from asymptomatic to severe disability. Our results showed a significant difference between NBS patients and clinical patients and the former had better outcome. Professional management of NBS programs and experienced genetic metabolic disease experts will be very important and urgent.\u003c/p\u003e"},{"header":"Methods ","content":"\u003cdiv id=\"Sec14\" class=\"Section2\"\u003e\n\u003ch2\u003ePatients\u003c/h2\u003e\n\u003cp\u003eWe focused on sixteen patients (nine females and seven males) with GA1 at the Third Affiliated Hospital of Zhengzhou University from January 2013 to December 2021. Six (four females and two males) of them were identified by newborn screening, whereas ten patients were admitted to screen because of suspected clinical symptoms. Two patients were siblings (patient N2 and C1). The age of these patients ranged from 15 months to 14 years. Informed consent was signed by the parents of GA1 patients and this research was approved by the Ethics Committee of The Third Affiliated Hospital of Zhengzhou University.(2019-67)\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec15\" class=\"Section2\"\u003e\n\u003ch2\u003eBiochemical Analysis\u003c/h2\u003e\n\u003cp\u003eDried blood spots on 903 filter paper ( Wallac Oy,Turku,Finland) were collected from all infants or suspected patients. Liquid chromatography-tandem mass spectrometer (LC-MS/MS) technology was used to detect the level of glutarylcarnitine (C5DC) and the C5DC/capryloylcarnitine (C8) rate of samples by tandem mass spectrometer (API 4000, American BioSystems, USA). Gas chromatography-mass spectrometry (GCMS-QP2010, Shimadzu, Japan) was used to quantify the glutaric acid (GA) and 3 hydroxyglutaric acid(3-OH-GA) in urine from suspected patients.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec16\" class=\"Section2\"\u003e\n\u003ch2\u003eGene Mutations Analysis\u003c/h2\u003e\n\u003cp\u003eThe genomic DNA of positive patients and their parents was isolated from peripheral blood leukocytes. The GCDH mutations of patients were detected by the next-generation sequencing panel, and parental mutations were verified by Sanger sequencing. Mutations were checked using the available databases HGMD (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.hgmd.cf.ac.uk\u003c/span\u003e\u003c/span\u003e), ClinVar (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttps://www.ncbi.nlm.nih.gov/clinvar)an\u003c/span\u003e\u003c/span\u003ed dbSNP (\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://www.ncbi.nlm.nih.gov/SNP/\u003c/span\u003e\u003c/span\u003e). PolyPhen2(\u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003ehttp://genetics.bwh.harvard.edu/pph2/\u003c/span\u003e\u003c/span\u003e), SIFT(Sorting Intolerant From Tolerant), REVEL (rare exome variant ensemble learner) and MutationTaster were used to predict the potential pathogenic effects of these variants.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec17\" class=\"Section2\"\u003e\n\u003ch2\u003eDisease Diagnosis\u003c/h2\u003e\n\u003cp\u003eIndividuals with high levels of C5DC and the C5DC/C8 ratio in the dried blood spots detected by LC-MS/MS were regarded as suspect patients. They were recalled to have second test. Rising level of C5DC in blood and increased excretion of GA and 3-OH-GA in urine combined with typical clinical features, general laboratory examinations provided strong evidences for the disease diagnosis. Patients were finally confirmed with GA1 by GCDH gene mutations analysis.\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec18\" class=\"Section2\"\u003e\n\u003ch2\u003eTreatment And Outcome\u003c/h2\u003e\n\u003cp\u003eIn consideration of early diagnosis and intervention for positive individuals, we adopted measures to diagnosis and treatment in the meantime. The treatment strategy included a restrict protein diet with special lysine /tryptophan-free formula before six years old and age-appropriate limited protein intake diet after six years of age. L-carnitine (50\u0026ndash;100 mg/kg/day)was supplemented everyday. Meanwhile, riboflavin (20\u0026ndash;200 mg/day) and emergency treatment were given if necessary[\u003cspan class=\"CitationRef\"\u003e2\u003c/span\u003e].\u003c/p\u003e\n\u003cp\u003eClinical data were collected through medical record and follow up. Using motor, cognition and speech score to evaluate clinical outcome. Motor disability was scored as 1 when no or mild motor dysfunction, as 2 when moderate motor dysfunction, and as 3 when severe disability that need wheelchair to assist or completely unable to move. Cognitive function was scored as 1 when normal or almost normal, as 2 when in the middle and as 3 when not normal or IQ was below 70. Speech function was scored as 1 when fluent or proximity fluent, as 2 when only with single words, and as 3 when speech absence. Sum up the scores from motor, cognition and speech as disability score to evaluate clinical outcome[\u003cspan class=\"CitationRef\"\u003e15\u003c/span\u003e].\u003c/p\u003e\n\u003c/div\u003e\n\u003cdiv id=\"Sec19\" class=\"Section2\"\u003e\n\u003ch2\u003eStatistical analysis\u003c/h2\u003e\n\u003cp\u003eStatistical analysis was executed with SPSS.21 (IBM, USA). The nonparametric Spearman rank correlation coefficient was used for correlation analysis. Mann-Whitney U test was used to compare outcomes between NBS group and non-NBS group. Statistical significance was identified when \u003cem\u003ep\u003c/em\u003e\u0026thinsp;\u0026lt;\u0026thinsp;0.05.\u003c/p\u003e\n\u003c/div\u003e"},{"header":"Abbreviations","content":"\u003cp\u003eGA1: Glutaric acidemia type 1\u003c/p\u003e\n\u003cp\u003eGCDH: glutaryl-CoA dehydrogenase\u003c/p\u003e\n\u003cp\u003eC5DC: glutarylcarnitine\u003c/p\u003e\n\u003cp\u003e3-OH-GA: 3-hydroxyglutaric acid\u003c/p\u003e\n\u003cp\u003eHGMD: Human Gene Mutation Database\u003c/p\u003e\n\u003cp\u003eC8: capryloylcarnitine\u003c/p\u003e\n\u003cp\u003eLC-MS/MS: Liquid chromatography-tandem mass spectrometer\u003c/p\u003e\n\u003cp\u003eNGS: Next-generation sequencing\u003c/p\u003e\n\u003cp\u003eSIFT: Sorting Intolerant From Tolerant\u003c/p\u003e\n\u003cp\u003eREVEL: rare exome variant ensemble learner\u003c/p\u003e\n\u003cp\u003eNBS: newborn screening\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003e\u003cstrong\u003eAvailability of data and materials\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe datasets used and/or analysed during the current study can be acquired from the corresponding author upon a reasonable request.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAcknowledgements\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eWe thank all the patients and their families for their participation.We thank all the laboratory and clinical staffs for their contributions to this study.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eAuthor contributions\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eXinyun Zhu performed the study design, data analysis, literature search and manuscript preparation. Xiaole Li, Yizhuo Xu and Linfei Li assisted with data collection, Suna Liu and Liting Jia assisted with revising the manuscript, Min Ni carried out LC/MS and GC/MS tests. Yaqing Guo performed the genetic tests and variants analysis. Dehua Zhao designed and supervised the research. All authors read and approved the final manuscript.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eFunding\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis work was funded by the Science and Technology Research Project of Henan Province [grant number SBGJ 202102182]; the Key R \u0026amp; D and Promotion Special Project of Henan Province [2121102310733];Medical Science and Technology Joint construction Project of Henan Province [LHGJ20190357];Medical Science and Technology Joint construction Project of Henan Province [LHGJ20200461];Medical Science and Technology Joint construction Project of Henan Province [LHGJ20200644];Medical Science and Technology Joint construction Project of Henan Province [LHGJ20210443]\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eEthics approval and consent to participate\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThis study was approved by the Ethical Committee of Ethics Committee of The Third Affiliated Hospital of Zhengzhou University. Written informed consent was obtained from the parents of all patients for collection of DBS samples and publication of medical data.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eConsent for publication\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eConsent was obtained from the parents of all patients for publication.\u003c/p\u003e\n\u003cp\u003e\u003cstrong\u003eCompeting interests\u003c/strong\u003e\u003c/p\u003e\n\u003cp\u003eThe authors declare that they have no competing interests.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n \u003cli\u003eKolker S, Garbade SF, Greenberg CR, Leonard JV, Saudubray JM, Ribes A, et al. Natural history, outcome, and treatment efficacy in children and adults with glutaryl-CoA dehydrogenase deficiency. Pediatr Res. 2006; 59(6):840-7.\u003c/li\u003e\n \u003cli\u003eBoy N, Muhlhausen C, Maier EM, Heringer J, Assmann B, Burgard P, et al. Proposed recommendations for diagnosing and managing individuals with glutaric aciduria type I: second revision. J Inherit Metab Dis. 2017; 40(1):75-101.\u003c/li\u003e\n \u003cli\u003eLin Y, Zheng Q, Zheng T, Zheng Z, Lin W, Fu Q. Expanded newborn screening for inherited metabolic disorders and genetic characteristics in a southern Chinese population. Clin Chim Acta. 2019; 494:106-11.\u003c/li\u003e\n \u003cli\u003eYang C, Zhou C, Xu P, Jin X, Liu W, Wang W, et al. Newborn screening and diagnosis of inborn errors of metabolism: A 5-year study in an eastern Chinese population. Clin Chim Acta. 2020; 502:133-8.\u003c/li\u003e\n \u003cli\u003eLin Y, Wang W, Lin C, Zheng Z, Fu Q, Peng W, et al. Biochemical and molecular features of Chinese patients with glutaric acidemia type 1 detected through newborn screening. Orphanet J Rare Dis. 2021; 16(1):339.\u003c/li\u003e\n \u003cli\u003eHeringer J, Boy SP, Ensenauer R, Assmann B, Zschocke J, Harting I, et al. Use of guidelines improves the neurological outcome in glutaric aciduria type I. Ann Neurol. 2010; 68(5):743-52.\u003c/li\u003e\n \u003cli\u003eStrauss KA, Puffenberger EG, Robinson DL, Morton DH. Type I glutaric aciduria, part 1: natural history of 77 patients. Am J Med Genet C Semin Med Genet. 2003; 121C(1):38-52.\u003c/li\u003e\n \u003cli\u003ePfeil J, Listl S, Hoffmann GF, Kolker S, Lindner M, Burgard P. Newborn screening by tandem mass spectrometry for glutaric aciduria type 1: a cost-effectiveness analysis. Orphanet J Rare Dis. 2013; 8:167.\u003c/li\u003e\n \u003cli\u003eGovender R, Mitha A, Mubaiwa L. A review of patients with glutaric aciduria type 1 at Inkosi Albert Luthuli Central Hospital, Durban, South Africa. S Afr Med J. 2017; 107(3):201-4.\u003c/li\u003e\n \u003cli\u003eBoy N, Mengler K, Thimm E, Schiergens KA, Marquardt T, Weinhold N, et al. Newborn screening: A disease-changing intervention for glutaric aciduria type 1. Ann Neurol. 2018; 83(5):970-9.\u003c/li\u003e\n \u003cli\u003eGoodman SI, Markey SP, Moe PG, Miles BS, Teng CC. Glutaric aciduria; a \u0026quot;new\u0026quot; disorder of amino acid metabolism. Biochem Med. 1975; 12(1):12-21.\u003c/li\u003e\n \u003cli\u003eZayed H, El Khayat H, Tomoum H, Khalifa O, Siddiq E, Mohammad SA, et al. Clinical, biochemical, neuroradiological and molecular characterization of Egyptian patients with glutaric acidemia type 1. Metab Brain Dis. 2019; 34(4):1231-41.\u003c/li\u003e\n \u003cli\u003eGurbuz BB, Yilmaz DY, Coskun T, Tokatli A, Dursun A, Sivri HS. Glutaric aciduria type 1: Genetic and phenotypic spectrum in 53 patients. Eur J Med Genet. 2020; 63(11):104032.\u003c/li\u003e\n \u003cli\u003eE H, Liang L, Zhang H, Qiu W, Ye J, Xu F, et al. Evaluation of the Clinical, Biochemical, Neurological, and Genetic Presentations of Glutaric Aciduria Type 1 in Patients From China. Front Genet. 2021; 12:702374.\u003c/li\u003e\n \u003cli\u003eKyllerman M, Skjeldal O, Christensen E, Hagberg G, Holme E, Lonnquist T, et al. Long-term follow-up, neurological outcome and survival rate in 28 Nordic patients with glutaric aciduria type 1. Eur J Paediatr Neurol. 2004; 8(3):121-9.\u003c/li\u003e\n \u003cli\u003eShi XT, Cai J, Wang YY, Tu WJ, Wang WP, Gong LM, et al. Newborn screening for inborn errors of metabolism in mainland china: 30 years of experience. JIMD Rep. 2012; 6:79-83.\u003c/li\u003e\n \u003cli\u003eYang L, Yin H, Yang R, Huang X. Diagnosis, treatment and outcome of glutaric aciduria type I in Zhejiang Province, China. Med Sci Monit. 2011; 17(7):PH55-9.\u003c/li\u003e\n \u003cli\u003eYang Y, Wang L, Wang B, Liu S, Yu B, Wang T. Application of Next-Generation Sequencing Following Tandem Mass Spectrometry to Expand Newborn Screening for Inborn Errors of Metabolism: A Multicenter Study. 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J Inherit Metab Dis. 2004; 27(6):861-8.\u003c/li\u003e\n \u003cli\u003ePokora P, Jezela-Stanek A, Rozdzynska-Swiatkowska A, Jurkiewicz E, Bogdanska A, Szymanska E, et al. Mild phenotype of glutaric aciduria type 1 in polish patients - novel data from a group of 13 cases. Metab Brain Dis. 2019; 34(2):641-9.\u003c/li\u003e\n \u003cli\u003eBoy N, Heringer J, Brackmann R, Bodamer O, Seitz A, Kolker S, et al. Extrastriatal changes in patients with late-onset glutaric aciduria type I highlight the risk of long-term neurotoxicity. Orphanet J Rare Dis. 2017; 12(1):77.\u003c/li\u003e\n \u003cli\u003eRenaud DL. Leukoencephalopathies associated with macrocephaly. Semin Neurol. 2012; 32(1):34-41.\u003c/li\u003e\n\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":true,"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":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Glutaric aciduria type 1, GCDH gene, glutarylcarnitine, restricted protein diet, mutations","lastPublishedDoi":"10.21203/rs.3.rs-1274419/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-1274419/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eGlutaric acidemia type 1 (GA1) is a rare organic acid metabolism disorder resulted from the deficiency of glutaryl-CoA dehydrogenase (GCDH). There are few studies on GA1 in China. This article is designed to investigate the clinical, biochemical and molecular characterizations of patients with GA1 in Henan province, in order to get further understanding of this disease .\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eResults:\u003c/strong\u003e The incidence of neonatal GA1 in Henan population was 1/172483. All patients had increased glutarylcarnitine (C5DC), glutaric acid (GA) and 3-hydroxyglutaric acid (3-OH-GA) levels. Twenty mutations were discovered in 14 patients. Four of them were novel: c.523G\u0026gt;A (p.G175S), c.1297G\u0026gt;C (p.A433P), c.467G\u0026gt;A (p.G156D) and c.1125T\u0026gt;G (p.C375W). The most common mutation was c.1064G\u0026gt;A (p.R355H), of which the allelic frequency was 17.86% (5/28), following by c.1109T\u0026gt;C (p.L370P), c.648G\u0026gt;A (p.S216S), c.395G\u0026gt;A (p.R132Q) and c.938G\u0026gt;A (p.R313Q), which had the same allelic frequency 7.14% (2/28). 84.6%(11/13) patients displayed abnormal brain MRI findings, of which cerebral dysplasia and arachnid/ependyma cysts(38.5%,5/13) were most commonly. Clinical features varied widely from asymptomatic to severe encephalopathy. Patients diagnosed by newborn screening had better outcome. A strong correlation was discovered among increasing disability in motor, speech and cognitive function. There were statistical significance differences in motor function(p=0.024) and speech function (p=0.008), but no statistical significance difference in cognitive function (p=0.106) between NBS group and non-NBS group.\u003c/p\u003e\u003cp\u003e\u003cstrong\u003eConclusions:\u003c/strong\u003e Our study provided comprehensive information about GA1 in Henan population, including morbidity, clinical, biochemical, molecular and outcome features. The novel variants expanded the GCDH variant spectra. This work emphasize that professional management of NBS programs and experienced genetic metabolic disease experts will be very important and urgent.\u003c/p\u003e","manuscriptTitle":"Clinical, Biochemical and Molecular Characterizations of Patients With Glutaric Aciduria Type 1 in Henan Province, China","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2022-03-09 20:27:38","doi":"10.21203/rs.3.rs-1274419/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"7797c5ce-d15d-4c9c-8a16-73a6dd657e57","owner":[],"postedDate":"March 9th, 2022","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2022-05-13T19:37:54+00:00","versionOfRecord":[],"versionCreatedAt":"2022-03-09 20:27:38","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-1274419","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-1274419","identity":"rs-1274419","version":["v1"]},"buildId":"cBFmMYwuxLRRLfASyISRj","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}