Genetic Identification and Molecular Characterization of an Eyes Absent (eya) Mutation Disrupting Compound Eye Development in Drosophila melanogaster

Genetic Identification and Molecular Characterization of an Eyes Absent (eya) Mutation Disrupting Compound Eye Development in Drosophila melanogaster | 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 Short Report Genetic Identification and Molecular Characterization of an Eyes Absent (eya) Mutation Disrupting Compound Eye Development in Drosophila melanogaster Joel Shah This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9088264/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 8 You are reading this latest preprint version Abstract Background: Drosophila melanogaster has long been valued as a model organism for studying the genetics underlying tissue differentiation, especially in the context of eye development. The formation of the fly’s compound eye is orchestrated by a group of genes known as the retinal determination gene network (RDGN), which includes key transcriptional regulators such as eyeless, sine oculis, dachshund, and eyes absent (eya). Results : Through a combination of classical genetic crosses, complementation testing, and PCR-based molecular assays, we identified a mutation in Drosophila melanogaster that results in the absence of compound eye structures. Notably, other head features such as antennae remained unaffected. The inheritance pattern observed in genetic crosses was recessive. Linkage analysis indicated that the mutation was associated with markers on chromosome 2. Complementation analysis demonstrated that the mutation complemented eyeless but did not complement a known eyes absent allele, suggesting the mutation is located at the eya locus. PCR amplification of the eya genomic region produced a fragment approximately 320 base pairs smaller than that of wild type, supporting the presence of a deletion in the eya gene. Conclusions: The data identify the eyes absent allele as the primary mutation responsible for the absence of compound eyes in the affected flies. These results underscore the essential role of eya within the retinal determination gene network during eye development in Drosophila melanogaster. Drosophila melanogaster eyes absent retinal determination gene network eye development genetic mapping PCR Figures Figure 1 Figure 2 Figure 3 Figure 4 Introduction Drosophila melanogaster has been a cornerstone of genetics and developmental biology research for more than a century. Many genes crucial to vertebrate development were first identified in these flies, and a significant number of human disease-associated genes have recognizable counterparts in Drosophila. The compound eye, made up of roughly 800 ommatidia, remains an invaluable system for exploring tissue patterning and photoreceptor differentiation. Eye development is governed by the retinal determination gene network (RDGN). Key members of this network include eyeless (Pax6), sine oculis, dachshund, and eyes absent (eya). These regulatory proteins coordinate gene expression programs required for retinal specification and photoreceptor differentiation. The eyes absent gene (eya) encodes a multifunctional transcriptional co-activator and a protein phosphatase. When eya function is lost, retinal development is disrupted, often leading to severe eye defects or the complete absence of compound eye structures. These observations highlight the gene’s critical contribution to normal eye formation. This study set out to identify and genetically characterize an unknown mutation impacting eye development in Drosophila melanogaster. Using classical genetic mapping, complementation analysis, and PCR-based molecular techniques, we sought to pinpoint the underlying genetic changes. Methods Wild-type strains, an unknown eye mutant, and marker strains (Cy/Pm;D/Sb) were obtained from the Bloomington Drosophila Stock Center. Flies were maintained on standard cornmeal medium at 25°C. Genetic crosses were performed to determine hereditary patterns and chromosomal linkage. Mutant females were crossed with wild-type males and marker strains. Progeny were scored using a stereomicroscope and grouped based on eye phenotype and visible genetic markers. Complementation tests were performed using strains carrying known eye development mutations, including eyeless and a characterized eyes absent allele. Genomic DNA was extracted from adult flies using alkaline lysis. PCR amplification of the eyes absent locus was performed, and products were analyzed by agarose gel electrophoresis. Results Mutant flies exhibited a phenotype characterized by the complete absence of compound eye structures, while other head features appeared morphologically normal as evidenced by genetic mapping (Figure 1). Crosses between mutant females and wild-type males produced exclusively wild-type F1 progeny, indicating recessive inheritance (Figure 2). Linkage analysis using chromosome marker strains demonstrated an association between the mutation and markers on chromosome 2 (Table 1). Complementation testing showed that the mutation complements eyeless but fails to complement a known eyes absent allele, demonstrating that the mutation occurs within the eya locus (Figure 3). PCR amplification of the eya genomic region produced a smaller fragment in mutant DNA relative to wild type, consistent with an approximately 320 bp deletion (Figure 4). Chi-square analysis supported segregation patterns compatible with recessive inheritance and linkage to chromosome 2 markers (Tables 3-6). Discussion The genetic and molecular evidence presented here indicates that the unknown mutation corresponds to an allele of the eyes absent ( eya ) gene. The absence of compound eye structures in mutant flies is consistent with the well-established role of eya in retinal determination and photoreceptor differentiation within the retinal determination gene network (RDGN) [1,3]. Previous studies have demonstrated that eya functions as a transcriptional co-activator that interacts with proteins such as Sine oculis and Dachshund to regulate gene expression programs required for retinal specification and differentiation [1–3]. Disruption of this regulatory module results in failure of eye field determination and loss of photoreceptor differentiation during development. Complementation testing provided strong genetic evidence for the mutation's identity. Failure to complement a known eya allele indicates that the mutation resides within the same locus rather than in another component of the RDGN pathway. PCR analysis additionally supports this conclusion by showing a smaller amplification product consistent with a deletion within the eya genomic region. Although the exact molecular lesion remains to be determined, deletions affecting coding sequences or regulatory elements of eya are expected to disrupt retinal specification during early eye disc development [2,3]. Because homologs of eya are conserved across metazoans, studies of eya function in Drosophila melanogaster continue to provide insight into conserved developmental routes. In humans, mutations in the orthologous gene EYA1 are associated with branchio-oto-renal syndrome, a developmental disorder affecting the ear and kidney [5,6]. These findings show the evolutionary conservation of mechanisms regulating organ development and demonstrate the continued value of Drosophila genetics for investigating fundamental developmental processes [4]. Limitations The mutation was identified using classical genetic analysis and PCR fragment analysis. However, DNA sequencing is necessary to determine the precise molecular lesion. Conclusion This study identifies a Drosophila eye mutation as an allele of eyes absent. Disruption of eya function prevents compound eye formation, underscoring the gene’s essential role in retinal development. Declarations Funding Declaration: The authors have no sources of funding to declare. References Bonini NM, Leiserson WM, Benzer S. The eyes absent gene: genetic control of cell survival and differentiation in the developing Drosophila eye. Cell. 1993 Feb 12;72(3):379-95. doi: 10.1016/0092-8674(93)90115-7. PMID: 8431945. Zimmerman JE, Bui QT, Liu H, Bonini NM. Molecular genetic analysis of Drosophila eyes absent mutants reveals an eye enhancer element. Genetics. 2000 Jan;154(1):237-46. doi: 10.1093/genetics/154.1.237. PMID: 10628984; PMCID: PMC1460909. Silver SJ, Davies EL, Doyon L, Rebay I. Functional dissection of eyes absent reveals new modes of regulation within the retinal determination gene network. Mol Cell Biol. 2003 Sep;23(17):5989-99. doi: 10.1128/MCB.23.17.5989-5999.2003. PMID: 12917324; PMCID: PMC180989. Bellen HJ, Tong C, Tsuda H. 100 years of Drosophila research and its impact on vertebrate neuroscience: a history lesson for the future. Nat Rev Neurosci. 2010 Jul;11(7):514-22. doi: 10.1038/nrn2839. PMID: 20383202; PMCID: PMC4022039. Azuma N, Hirakiyama A, Inoue T, Asaka A, Yamada M. Mutations of a human homologue of the Drosophila eyes absent gene (EYA1) detected in patients with congenital cataracts and ocular anterior segment anomalies. Hum Mol Genet. 2000 Feb 12;9(3):363-6. doi: 10.1093/hmg/9.3.363. PMID: 10655545. Abdelhak S, Kalatzis V, Heilig R, Compain S, Samson D, Vincent C, Weil D, Cruaud C, Sahly I, Leibovici M, Bitner-Glindzicz M, Francis M, Lacombe D, Vigneron J, Charachon R, Boven K, Bedbeder P, Van Regemorter N, Weissenbach J, Petit C. A human homologue of the Drosophila eyes absent gene underlies branchio-oto-renal (BOR) syndrome and identifies a novel gene family. Nat Genet. 1997 Feb;15(2):157-64. doi: 10.1038/ng0297-157. PMID: 9020840. Tables Tables are available as a supplementary file. Additional Declarations No competing interests reported. Supplementary Files Tables.docx Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 07 Apr, 2026 Reviews received at journal 01 Apr, 2026 Reviewers agreed at journal 21 Mar, 2026 Reviewers invited by journal 19 Mar, 2026 Editor invited by journal 18 Mar, 2026 Editor assigned by journal 17 Mar, 2026 Submission checks completed at journal 17 Mar, 2026 First submitted to journal 10 Mar, 2026 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. We do this by developing innovative software and high quality services for the global research community. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9088264","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Short Report","associatedPublications":[],"authors":[{"id":610082848,"identity":"94a4dea3-e4bc-4c0c-aa3c-aa9c5e76aa17","order_by":0,"name":"Joel Shah","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAAA3UlEQVRIiWNgGAWjYBACxgYGxgNAIoEfyGGGiCUQ1MIA1iLZxkykFhAAazE4RqwW5vbmAwd/7rDLM77ff0y64I8dAz97jgF+h/UcSzjMeya52OwYM5v0zLZkBsmeNwS0zMgxOMzYxpy4DaSFt+EAg8ENQrbMyP9w8GdbfeLmNqAWnj8HGOwJa8lhOMDbdjhxAxtICxvQFgnCfjE4zNt2PHHGsWRja962ZB6JM88K8GoxbG9++PBnW3Vif/PBh7d5/tjJ8bcnb8CvpQFNgAevchCQJ6hiFIyCUTAKRgEAdnFItzJmA74AAAAASUVORK5CYII=","orcid":"","institution":"Texas Tech University Health Sciences Center El Paso","correspondingAuthor":true,"prefix":"","firstName":"Joel","middleName":"","lastName":"Shah","suffix":""}],"badges":[],"createdAt":"2026-03-10 23:54:01","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9088264/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9088264/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":105898494,"identity":"b15292c5-38c3-41df-a300-9669e048c3a6","added_by":"auto","created_at":"2026-04-01 09:05:00","extension":"png","order_by":1,"title":"Figure 1","display":"","copyAsset":false,"role":"figure","size":120600,"visible":true,"origin":"","legend":"\u003cp\u003eDiagram showing the \u003cstrong\u003ediscriminant cross used for genetic mapping on Chromosome 2 in \u003c/strong\u003e\u003cem\u003eDrosophila\u003c/em\u003e utilizing three markers: \u003cstrong\u003eeya (eyeless)\u003c/strong\u003e located on chromosome 2, \u003cstrong\u003ePm (Plum)\u003c/strong\u003e located on chromosome 2, \u003cstrong\u003eSb (Stubble) \u003c/strong\u003elocated on chromosome 3.\u003c/p\u003e","description":"","filename":"1.png","url":"https://assets-eu.researchsquare.com/files/rs-9088264/v1/d3fd876b70d3824cb88ddb17.png"},{"id":105898498,"identity":"9bd8fe3b-808e-4ff2-9df0-5ca93a84d4c4","added_by":"auto","created_at":"2026-04-01 09:05:00","extension":"png","order_by":2,"title":"Figure 2","display":"","copyAsset":false,"role":"figure","size":345017,"visible":true,"origin":"","legend":"\u003cp\u003eComplementation test between eyeless (A) and the unknown mutation (B) producing wild-type progeny (C and D). Both eyeless and the unknown mutation appear to be recessive in nature.\u003c/p\u003e","description":"","filename":"2.png","url":"https://assets-eu.researchsquare.com/files/rs-9088264/v1/5e0d50af34fd147881d5df54.png"},{"id":105898496,"identity":"500f778d-3502-4f63-849a-6c0616925f3b","added_by":"auto","created_at":"2026-04-01 09:05:00","extension":"png","order_by":3,"title":"Figure 3","display":"","copyAsset":false,"role":"figure","size":488608,"visible":true,"origin":"","legend":"\u003cp\u003eComplementation test between two eyes absent alleles (A and B) demonstrating allelism (C and D). The cross of A and B generate progeny C and D.\u003c/p\u003e","description":"","filename":"3.png","url":"https://assets-eu.researchsquare.com/files/rs-9088264/v1/4ea7e780e484630d6705e39b.png"},{"id":105906801,"identity":"1f504e1f-5148-4344-a457-131428d95bd8","added_by":"auto","created_at":"2026-04-01 10:25:08","extension":"png","order_by":4,"title":"Figure 4","display":"","copyAsset":false,"role":"figure","size":555998,"visible":true,"origin":"","legend":"\u003cp\u003ePCR gel electrophoresis showing a reduced fragment size in mutant DNA relative to wild type, consistent with a deletion in the eyes absent locus.\u003c/p\u003e","description":"","filename":"4.png","url":"https://assets-eu.researchsquare.com/files/rs-9088264/v1/75c1bfc45bc05da262785eaa.png"},{"id":105909879,"identity":"52a8d9dd-5066-4b87-b8a1-965f10d0596b","added_by":"auto","created_at":"2026-04-01 10:45:26","extension":"pdf","order_by":0,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":2469922,"visible":true,"origin":"","legend":"","description":"","filename":"manuscript.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9088264/v1/ea816a14-94b7-4c1b-8093-d7a650d868fd.pdf"},{"id":105898495,"identity":"77385da6-8157-4b28-a764-3f5dd92eaf94","added_by":"auto","created_at":"2026-04-01 09:05:00","extension":"docx","order_by":1,"title":"","display":"","copyAsset":false,"role":"supplement","size":17775,"visible":true,"origin":"","legend":"","description":"","filename":"Tables.docx","url":"https://assets-eu.researchsquare.com/files/rs-9088264/v1/da2df14550987d5983fda5b5.docx"}],"financialInterests":"No competing interests reported.","formattedTitle":"Genetic Identification and Molecular Characterization of an Eyes Absent (eya) Mutation Disrupting Compound Eye Development in Drosophila melanogaster","fulltext":[{"header":"Introduction","content":"\u003cp\u003eDrosophila melanogaster has been a cornerstone of genetics and developmental biology research for more than a century. Many genes crucial to vertebrate development were first identified in these flies, and a significant number of human disease-associated genes have recognizable counterparts in Drosophila. The compound eye, made up of roughly 800 ommatidia, remains an invaluable system for exploring tissue patterning and photoreceptor differentiation.\u003cbr\u003e \u003cbr\u003e Eye development is governed by the retinal determination gene network (RDGN). Key members of this network include eyeless (Pax6), sine oculis, dachshund, and eyes absent (eya). These regulatory proteins coordinate gene expression programs required for retinal specification and photoreceptor differentiation.\u003cbr\u003e \u003cbr\u003e The eyes absent gene (eya) encodes a multifunctional transcriptional co-activator and a protein phosphatase. When eya function is lost, retinal development is disrupted, often leading to severe eye defects or the complete absence of compound eye structures. These observations highlight the gene’s critical contribution to normal eye formation.\u003cbr\u003e \u003cbr\u003e This study set out to identify and genetically characterize an unknown mutation impacting eye development in Drosophila melanogaster. Using classical genetic mapping, complementation analysis, and PCR-based molecular techniques, we sought to pinpoint the underlying genetic changes.\u003c/p\u003e"},{"header":"Methods","content":"\u003cp\u003eWild-type strains, an unknown eye mutant, and marker strains (Cy/Pm;D/Sb) were obtained from the Bloomington Drosophila Stock Center. Flies were maintained on standard cornmeal medium at 25°C.\u003cbr\u003e \u003cbr\u003e Genetic crosses were performed to determine hereditary patterns and chromosomal linkage. Mutant females were crossed with wild-type males and marker strains. Progeny were scored using a stereomicroscope and grouped based on eye phenotype and visible genetic markers.\u003cbr\u003e \u003cbr\u003e Complementation tests were performed using strains carrying known eye development mutations, including eyeless and a characterized eyes absent allele.\u003cbr\u003e \u003cbr\u003e Genomic DNA was extracted from adult flies using alkaline lysis. PCR amplification of the eyes absent locus was performed, and products were analyzed by agarose gel electrophoresis.\u003c/p\u003e"},{"header":"Results","content":"\u003cp\u003eMutant flies exhibited a phenotype characterized by the complete absence of compound eye structures, while other head features appeared morphologically normal as evidenced by genetic mapping (Figure 1).\u003cbr\u003e \u003cbr\u003e Crosses between mutant females and wild-type males produced exclusively wild-type F1 progeny, indicating recessive inheritance (Figure 2).\u003cbr\u003e \u003cbr\u003e Linkage analysis using chromosome marker strains demonstrated an association between the mutation and markers on chromosome 2 (Table 1).\u003cbr\u003e \u003cbr\u003e Complementation testing showed that the mutation complements eyeless but fails to complement a known eyes absent allele, demonstrating that the mutation occurs within the eya locus (Figure 3).\u003cbr\u003e \u003cbr\u003e PCR amplification of the eya genomic region produced a smaller fragment in mutant DNA relative to wild type, consistent with an approximately 320 bp deletion (Figure 4). Chi-square analysis supported segregation patterns compatible with recessive inheritance and linkage to chromosome 2 markers (Tables 3-6).\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eThe genetic and molecular evidence presented here indicates that the unknown mutation corresponds to an allele of the \u003cem\u003eeyes absent\u003c/em\u003e (\u003cem\u003eeya\u003c/em\u003e) gene. The absence of compound eye structures in mutant flies is consistent with the well-established role of \u003cem\u003eeya\u003c/em\u003e in retinal determination and photoreceptor differentiation within the retinal determination gene network (RDGN) [1,3]. Previous studies have demonstrated that \u003cem\u003eeya\u003c/em\u003e functions as a transcriptional co-activator that interacts with proteins such as Sine oculis and Dachshund to regulate gene expression programs required for retinal specification and differentiation [1–3]. Disruption of this regulatory module results in failure of eye field determination and loss of photoreceptor differentiation during development.\u003c/p\u003e\n\u003cp\u003eComplementation testing provided strong genetic evidence for the mutation's identity. Failure to complement a known \u003cem\u003eeya\u003c/em\u003e allele indicates that the mutation resides within the same locus rather than in another component of the RDGN pathway. PCR analysis additionally supports this conclusion by showing a smaller amplification product consistent with a deletion within the \u003cem\u003eeya\u003c/em\u003e genomic region. Although the exact molecular lesion remains to be determined, deletions affecting coding sequences or regulatory elements of \u003cem\u003eeya\u003c/em\u003e are expected to disrupt retinal specification during early eye disc development [2,3].\u003c/p\u003e\n\u003cp\u003eBecause homologs of \u003cem\u003eeya\u003c/em\u003e are conserved across metazoans, studies of \u003cem\u003eeya\u003c/em\u003e function in Drosophila melanogaster continue to provide insight into conserved developmental routes. In humans, mutations in the orthologous gene \u003cem\u003eEYA1\u003c/em\u003e are associated with branchio-oto-renal syndrome, a developmental disorder affecting the ear and kidney [5,6]. These findings show the evolutionary conservation of mechanisms regulating organ development and demonstrate the continued value of Drosophila genetics for investigating fundamental developmental processes [4].\u003c/p\u003e\n\u003ch1\u003e\u003cu\u003eLimitations\u003c/u\u003e\u003c/h1\u003e\n\u003cp\u003eThe mutation was identified using classical genetic analysis and PCR fragment analysis. However, DNA sequencing is necessary to determine the precise molecular lesion.\u003c/p\u003e"},{"header":"Conclusion","content":"\u003cp\u003eThis study identifies a Drosophila eye mutation as an allele of eyes absent. Disruption of eya function prevents compound eye formation, underscoring the gene\u0026rsquo;s essential role in retinal development.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eFunding Declaration: The authors have no sources of funding to declare.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\n\u003cli\u003eBonini NM, Leiserson WM, Benzer S. The eyes absent gene: genetic control of cell survival and differentiation in the developing Drosophila eye. Cell. 1993 Feb 12;72(3):379-95. doi: 10.1016/0092-8674(93)90115-7. PMID: 8431945.\u003c/li\u003e\n\u003cli\u003eZimmerman JE, Bui QT, Liu H, Bonini NM. Molecular genetic analysis of Drosophila eyes absent mutants reveals an eye enhancer element. Genetics. 2000 Jan;154(1):237-46. doi: 10.1093/genetics/154.1.237. PMID: 10628984; PMCID: PMC1460909.\u003c/li\u003e\n\u003cli\u003eSilver SJ, Davies EL, Doyon L, Rebay I. Functional dissection of eyes absent reveals new modes of regulation within the retinal determination gene network. Mol Cell Biol. 2003 Sep;23(17):5989-99. doi: 10.1128/MCB.23.17.5989-5999.2003. PMID: 12917324; PMCID: PMC180989.\u003c/li\u003e\n\u003cli\u003eBellen HJ, Tong C, Tsuda H. 100 years of Drosophila research and its impact on vertebrate neuroscience: a history lesson for the future. Nat Rev Neurosci. 2010 Jul;11(7):514-22. doi: 10.1038/nrn2839. PMID: 20383202; PMCID: PMC4022039.\u003c/li\u003e\n\u003cli\u003eAzuma N, Hirakiyama A, Inoue T, Asaka A, Yamada M. Mutations of a human homologue of the Drosophila eyes absent gene (EYA1) detected in patients with congenital cataracts and ocular anterior segment anomalies. Hum Mol Genet. 2000 Feb 12;9(3):363-6. doi: 10.1093/hmg/9.3.363. PMID: 10655545.\u003c/li\u003e\n\u003cli\u003eAbdelhak S, Kalatzis V, Heilig R, Compain S, Samson D, Vincent C, Weil D, Cruaud C, Sahly I, Leibovici M, Bitner-Glindzicz M, Francis M, Lacombe D, Vigneron J, Charachon R, Boven K, Bedbeder P, Van Regemorter N, Weissenbach J, Petit C. A human homologue of the Drosophila eyes absent gene underlies branchio-oto-renal (BOR) syndrome and identifies a novel gene family. Nat Genet. 1997 Feb;15(2):157-64. doi: 10.1038/ng0297-157. PMID: 9020840.\u003c/li\u003e\n\u003c/ol\u003e"},{"header":"Tables","content":"Tables are available as a supplementary file."}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"bmc-research-notes","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"resn","sideBox":"Learn more about [BMC Research Notes](http://bmcresnotes.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/resn/default.aspx","title":"BMC Research Notes","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Drosophila melanogaster, eyes absent, retinal determination gene network, eye development, genetic mapping, PCR","lastPublishedDoi":"10.21203/rs.3.rs-9088264/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9088264/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003e\u003cstrong\u003eBackground: \u003c/strong\u003eDrosophila melanogaster has long been valued as a model organism for studying the genetics underlying tissue differentiation, especially in the context of eye development. The formation of the fly’s compound eye is orchestrated by a group of genes known as the retinal determination gene network (RDGN), which includes key transcriptional regulators such as eyeless, sine oculis, dachshund, and eyes absent (eya).\u003cbr\u003e\n \u003cstrong\u003eResults\u003c/strong\u003e: Through a combination of classical genetic crosses, complementation testing, and PCR-based molecular assays, we identified a mutation in Drosophila melanogaster that results in the absence of compound eye structures. Notably, other head features such as antennae remained unaffected. The inheritance pattern observed in genetic crosses was recessive. Linkage analysis indicated that the mutation was associated with markers on chromosome 2. Complementation analysis demonstrated that the mutation complemented eyeless but did not complement a known eyes absent allele, suggesting the mutation is located at the eya locus. PCR amplification of the eya genomic region produced a fragment approximately 320 base pairs smaller than that of wild type, supporting the presence of a deletion in the eya gene.\u003cbr\u003e\n\u003cstrong\u003e Conclusions: \u003c/strong\u003eThe data identify the eyes absent allele as the primary mutation responsible for the absence of compound eyes in the affected flies. These results underscore the essential role of eya within the retinal determination gene network during eye development in Drosophila melanogaster.\u003c/p\u003e","manuscriptTitle":"Genetic Identification and Molecular Characterization of an Eyes Absent (eya) Mutation Disrupting Compound Eye Development in Drosophila melanogaster","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-01 09:04:56","doi":"10.21203/rs.3.rs-9088264/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-07T08:04:25+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-01T22:26:14+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"89785907253964352724754785628414445594","date":"2026-03-21T21:48:42+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-03-19T21:05:52+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-03-18T14:56:47+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-03-17T14:17:39+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-03-17T14:16:49+00:00","index":"","fulltext":""},{"type":"submitted","content":"BMC Research Notes","date":"2026-03-10T23:43:09+00:00","index":"","fulltext":""}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"bmc-research-notes","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"resn","sideBox":"Learn more about [BMC Research Notes](http://bmcresnotes.biomedcentral.com)","snPcode":"","submissionUrl":"https://www.editorialmanager.com/resn/default.aspx","title":"BMC Research Notes","twitterHandle":"@BMC_series","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"em","reportingPortfolio":"BMC Series","inReviewEnabled":true,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"ccc5c087-2d26-4627-a317-40e77f2192a1","owner":[],"postedDate":"April 1st, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[],"tags":[],"updatedAt":"2026-05-02T10:08:12+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-01 09:04:56","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9088264","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9088264","identity":"rs-9088264","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}