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Lecca M, Mauri L, Gana S, Del Longo A, Morelli F, Nicotra R, Plumari M, Galli J, Sirchia F, Valente EM, Cavallari U, Mazza M, Signorini S, Errichiello E. Novel molecular, structural and clinical findings in an Italian cohort of congenital cataract. Clin Genet 2024. [PMID: 38840272 DOI: 10.1111/cge.14568] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2024] [Revised: 05/16/2024] [Accepted: 05/24/2024] [Indexed: 06/07/2024]
Abstract
The current genetic diagnostic workup of congenital cataract (CC) is mainly based on NGS panels, whereas exome sequencing (ES) has occasionally been employed. In this multicentre study, we investigated by ES the detection yield, mutational spectrum and genotype-phenotype correlations in a CC cohort recruited between 2020 and mid-2022. The cohort consisted of 67 affected individuals from 51 unrelated families and included both non-syndromic (75%) and syndromic (25%) phenotypes, with extra-CC ocular/visual features present in both groups (48% and 76%, respectively). The functional effect of variants was predicted by 3D modelling and hydropathy properties changes. Variant clustering was used for the in-depth assessment of genotype-phenotype correlations. A diagnostic (pathogenic or likely pathogenic) variant was identified in 19 out of 51 probands/families (~37%). In a further 14 probands/families a candidate variant was identified: in 12 families a VUS was detected, of which 9 were considered plausibly pathogenic (i.e., 4 or 5 points according to ACMG criteria), while in 2 probands ES identified a single variant in an autosomal recessive gene associated with CC. Eighteen probands/families, manifesting primarily non-syndromic CC (15/18, 83%), remained unsolved. The identified variants (8 P, 12 LP, 10 VUS-PP, and 5 VUS), half of which were unreported in the literature, affected five functional categories of genes involved in transcription/splicing, lens formation/homeostasis (i.e., crystallin genes), membrane signalling, cell-cell interaction, and immune response. A phenotype-specific variant clustering was observed in four genes (KIF1A, MAF, PAX6, SPTAN1), whereas variable expressivity and potential phenotypic expansion in two (BCOR, NHS) and five genes (CWC27, KIF1A, IFIH1, PAX6, SPTAN1), respectively. Finally, ES allowed to detect variants in six genes not commonly included in commercial CC panels. These findings broaden the genotype-phenotype correlations in one of the largest CC cohorts tested by ES, providing novel insights into the underlying pathogenetic mechanisms and emphasising the power of ES as first-tier test.
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Affiliation(s)
- Mauro Lecca
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
| | - Lucia Mauri
- Medical Genetics Unit, Department of Laboratory Medicine, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Simone Gana
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Alessandra Del Longo
- Pediatric Ophthalmology Unit, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
- European Reference Network on Eye Diseases (ERN-EYE), ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Federica Morelli
- Developmental Neuro-ophthalmology Unit, IRCCS Mondino Foundation, Pavia, Italy
- Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy
| | - Roberta Nicotra
- Developmental Neuro-ophthalmology Unit, IRCCS Mondino Foundation, Pavia, Italy
- Department of Brain and Behavioural Sciences, University of Pavia, Pavia, Italy
| | - Massimo Plumari
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Jessica Galli
- Department of Clinical and Experimental Sciences, University of Brescia, Brescia, Italy
- Unit of Child Neurology and Psychiatry, ASST Spedali Civili of Brescia, Brescia, Italy
| | - Fabio Sirchia
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Medical Genetics Unit, IRCCS San Matteo Foundation, Pavia, Italy
| | - Enza Maria Valente
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Ugo Cavallari
- Medical Genetics Unit, Department of Laboratory Medicine, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Marco Mazza
- Pediatric Ophthalmology Unit, ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
- European Reference Network on Eye Diseases (ERN-EYE), ASST Grande Ospedale Metropolitano Niguarda, Milan, Italy
| | - Sabrina Signorini
- Developmental Neuro-ophthalmology Unit, IRCCS Mondino Foundation, Pavia, Italy
| | - Edoardo Errichiello
- Department of Molecular Medicine, University of Pavia, Pavia, Italy
- Medical Genetics Unit, IRCCS Mondino Foundation, Pavia, Italy
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Sun Q, Li J, Ma J, Zheng Y, Ju R, Li X, Ren X, Huang L, Chen R, Tan X, Luo L. JAM-C Is Important for Lens Epithelial Cell Proliferation and Lens Fiber Maturation in Murine Lens Development. Invest Ophthalmol Vis Sci 2023; 64:15. [PMID: 38095908 PMCID: PMC10723223 DOI: 10.1167/iovs.64.15.15] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2023] [Accepted: 11/16/2023] [Indexed: 12/17/2023] Open
Abstract
Purpose The underlying mechanism of congenital cataracts caused by deficiency or mutation of junctional adhesion molecule C (JAM-C) gene remains unclear. Our study aims to elucidate the abnormal developmental process in Jamc-/- lenses and reveal the genes related to lens development that JAM-C may regulate. Methods Jamc knockout (Jamc-/-) mouse embryos and pups were generated for in vivo studies. Four key developmental stages from embryonic day (E) 12.5 to postnatal day (P) 0.5 were selected for the following experiments. Hematoxylin and eosin staining was used for histological analysis. The 5-bromo-2'-deoxyuridine (BrdU) incorporation assay and TUNEL staining were performed to label lens epithelial cell (LEC) proliferation and apoptosis, respectively. Immunofluorescence and Western blot were used to analyze the markers of lens epithelium, cell cycle exit, and lens fiber differentiation. Results JAM-C was expressed throughout the process of lens development. Deletion of Jamc resulted in decreased lens size and disorganized lens fibers, which arose from E16.5 and aggravated gradually. The LECs of Jamc-/- lenses showed decreased quantity and proliferation, accompanied with reduction of key transcription factor, FOXE3. The fibers in Jamc-/- lenses were disorganized. Moreover, Jamc-deficient lens fibers showed significantly altered distribution patterns of Cx46 and Cx50. The marker of fiber homeostasis, γ-crystallin, was also decreased in the inner cortex and core fibers of Jamc-/- lenses. Conclusions Deletion of JAM-C exhibits malfunction of LEC proliferation and fiber maturation during murine lens development, which may be related to the downregulation of FOXE3 expression and abnormal localization patterns of Cx46 and Cx50.
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Affiliation(s)
- Qihang Sun
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Jiani Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Jingyu Ma
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Yuxing Zheng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Rong Ju
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xuri Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xiangrong Ren
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Lijuan Huang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Rongyuan Chen
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Xuhua Tan
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Lixia Luo
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
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Wang KJ, Wang JX, Wang JD, Li M, Zhang JS, Mao YY, Wan XH. Congenital coralliform cataract is the predominant consequence of a recurrent mutation in the CRYGD gene. Orphanet J Rare Dis 2023; 18:200. [PMID: 37480084 PMCID: PMC10362579 DOI: 10.1186/s13023-023-02816-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2022] [Accepted: 07/08/2023] [Indexed: 07/23/2023] Open
Abstract
BACKGROUND Congenital cataract is a leading cause of treatable childhood blindness and both clinically and genetically heterogeneous. Among the already characterized phenotypes, coralliform cataract is a rare special form of congenital cataracts. Although previous studies had shown that mutations in the γD-crystallin (CRYGD) can result in congenital coralliform cataracts, no conclusive genotype-phenotype correlation might be drawn. Here we aimed to identify the spectrum and frequency of CRYGD gene mutations in congenital coralliform cataracts of Chinese origin. METHODS The medical records of 392 Chinese families with congenital cataracts were reviewed between January 2011 and December 2021. The families, clinically documented to have congenital coralliform cataracts, were screened for mutations in candidate CRYGD gene. The genomic DNA of all subjects was extracted from peripheral blood leukocytes. PCR amplified and direct sequencing were performed to identify the disease-causing mutation. RESULTS A total of 12 families with coralliform cataracts were recruited in this study in the past 10 years, accounting for 3.1% of the families with congenital cataracts. Of the 12 families, all affected individuals presented with bilateral non-progressive coralliform cataracts since birth, with the best-corrected Snellen visual acuities ranging from 20/200 to 20/25. A recurrent c.70 C > A (p. P24T) mutation in CRYGD was identified in 10 families (83.3%) with congenital cataract, which co-segregated with all affected individuals and was not observed in unaffected family members or ethnically matched normal controls. CONCLUSIONS The coralliform cataract is characterized by being bilateral, non-progressive and present at birth. A recurrent p.P24T CRYGD mutation occurs independently in 83.3% of the Chinese families with congenital coralliform cataracts and most likely represents a mutational hot spot, which underscore the relations between coralliform cataract and p.P24T CRYGD.
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Affiliation(s)
- Kai-Jie Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, 100730, Beijing, China
| | - Jue-Xue Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, 100730, Beijing, China
| | - Jin-Da Wang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, 100730, Beijing, China
| | - Meng Li
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, 100730, Beijing, China
| | - Jing-Shang Zhang
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, 100730, Beijing, China
| | - Ying-Yan Mao
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, 100730, Beijing, China
| | - Xiu-Hua Wan
- Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology & Visual Sciences Key Lab, 100730, Beijing, China.
- NO.1 Dong Jiao Min Xiang, 100730, Beijing, China.
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Bennett TM, Zhou Y, Meyer KJ, Anderson MG, Shiels A. Whole-exome sequencing prioritizes candidate genes for hereditary cataract in the Emory mouse mutant. G3 (BETHESDA, MD.) 2023; 13:jkad055. [PMID: 36891866 PMCID: PMC10151407 DOI: 10.1093/g3journal/jkad055] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2023] [Revised: 02/20/2023] [Accepted: 02/28/2023] [Indexed: 03/10/2023]
Abstract
The Emory cataract (Em) mouse mutant has long been proposed as an animal model for age-related or senile cataract in humans-a leading cause of visual impairment. However, the genetic defect(s) underlying the autosomal dominant Em phenotype remains elusive. Here, we confirmed development of the cataract phenotype in commercially available Em/J mice [but not ancestral Carworth Farms White (CFW) mice] at 6-8 months of age and undertook whole-exome sequencing of candidate genes for Em. Analysis of coding and splice-site variants did not identify any disease-causing/associated mutations in over 450 genes known to underlie inherited and age-related forms of cataract and other lens disorders in humans and mice, including genes for lens crystallins, membrane/cytoskeleton proteins, DNA/RNA-binding proteins, and those associated with syndromic/systemic forms of cataract. However, we identified three cataract/lens-associated genes each with one novel homozygous variant including predicted missense substitutions in Prx (p.R167C) and Adamts10 (p.P761L) and a disruptive in-frame deletion variant (predicted missense) in Abhd12 (p.L30_A32delinsS) that were absent in CFW and over 35 other mouse strains. In silico analysis predicted that the missense substitutions in Prx and Adamts10 were borderline neutral/damaging and neutral, respectively, at the protein function level, whereas, that in Abhd12 was functionally damaging. Both the human counterparts of Adamts10 and Abhd12 are clinically associated with syndromic forms of cataract known as Weil-Marchesani syndrome 1 and polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and cataract syndrome, respectively. Overall, while we cannot exclude Prx and Adamts10, our data suggest that Abhd12 is a promising candidate gene for cataract in the Em/J mouse.
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Affiliation(s)
- Thomas M Bennett
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Yuefang Zhou
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
| | - Kacie J Meyer
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Michael G Anderson
- Department of Molecular Physiology and Biophysics, Carver College of Medicine, University of Iowa, Iowa City, IA 52242, USA
| | - Alan Shiels
- Department of Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO 63110, USA
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Shojima N, Yamauchi T. Progress in genetics of type 2 diabetes and diabetic complications. J Diabetes Investig 2023; 14:503-515. [PMID: 36639962 PMCID: PMC10034958 DOI: 10.1111/jdi.13970] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/28/2022] [Revised: 12/12/2022] [Accepted: 12/15/2022] [Indexed: 01/15/2023] Open
Abstract
Type 2 diabetes results from a complex interaction between genetic and environmental factors. Precision medicine for type 2 diabetes using genetic data is expected to predict the risk of developing diabetes and complications and to predict the effects of medications and life-style intervention more accurately for individuals. Genome-wide association studies (GWAS) have been conducted in European and Asian populations and new genetic loci have been identified that modulate the risk of developing type 2 diabetes. Novel loci were discovered by GWAS in diabetic complications with increasing sample sizes. Large-scale genome-wide association analysis and polygenic risk scores using biobank information is making it possible to predict the development of type 2 diabetes. In the ADVANCE clinical trial of type 2 diabetes, a multi-polygenic risk score was useful to predict diabetic complications and their response to treatment. Proteomics and metabolomics studies have been conducted and have revealed the associations between type 2 diabetes and inflammatory signals and amino acid synthesis. Using multi-omics analysis, comprehensive molecular mechanisms have been elucidated to guide the development of targeted therapy for type 2 diabetes and diabetic complications.
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Affiliation(s)
- Nobuhiro Shojima
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
| | - Toshimasa Yamauchi
- Department of Diabetes and Metabolic Diseases, Graduate School of Medicine, The University of Tokyo, Tokyo, Japan
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Asghari M, Abedini S, Farshidianfar M, Tajbakhsh A, Derakhshan A, Pasdar A. Identification of a Missense Mutation in GJA8 Gene in an Iranian Family with Autosomal Dominant Congenital Cataract. J Curr Ophthalmol 2023; 35:73-78. [PMID: 37680296 PMCID: PMC10481974 DOI: 10.4103/joco.joco_2_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/03/2022] [Revised: 12/20/2022] [Accepted: 12/20/2022] [Indexed: 09/09/2023] Open
Abstract
Purpose To identify the causative mutations of autosomal dominant (AD) congenital cataracts in a large Iranian family. Methods The complete and accurate family history and clinical information of participants were collected. A total of 51 family members, including 22 affected and 29 unaffected individuals, were recruited in this study. We performed whole exome sequencing to reveal pathogenic mutation. We used amplification refractory mutation system polymerase chain reaction and Sanger sequencing techniques to confirm segregation in patients and also to rule it out in the healthy participants. Results A known missense mutation, c.827C>T (S276F), in GJA8 was identified. This mutation was confirmed in all patients. Neither all healthy family members nor 100 healthy individuals who served as controls from general population had this mutation. Conclusion The missense mutation c. 827C>T in the GJA8 gene is associated with AD congenital lamellar cataract with complete penetrance in a six-generation Iranian family.
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Affiliation(s)
- Mahla Asghari
- Department of Medical Genetics and Molecular Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Soheila Abedini
- Department of Medical Genetics and Molecular Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
| | | | - Amir Tajbakhsh
- Department of Medical Genetics and Molecular Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Pharmaceutical Sciences Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Akbar Derakhshan
- Department of Ophthalmology, Mashhad University of Medical Sciences, Mashhad, Iran
| | - Alireza Pasdar
- Department of Medical Genetics and Molecular Medicine, Faculty of Medicine, Mashhad University of Medical Sciences, Mashhad, Iran
- Division of Applied Medicine, Medical School, University of Aberdeen, Aberdeen, Scotland, UK
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Jones JL, Burdon KP. Evaluating gap junction variants for a role in pediatric cataract: an overview of the genetic landscape and clinical classification of variants in the GJA3 and GJA8 genes. EXPERT REVIEW OF OPHTHALMOLOGY 2022. [DOI: 10.1080/17469899.2023.2160320] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Affiliation(s)
- Johanna L Jones
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
| | - Kathryn P Burdon
- Menzies Institute for Medical Research, University of Tasmania, Hobart, Tasmania, Australia
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Jaradat R, Li X, Chen H, Stathopulos PB, Bai D. The Hydrophobic Residues in Amino Terminal Domains of Cx46 and Cx50 Are Important for Their Gap Junction Channel Ion Permeation and Gating. Int J Mol Sci 2022; 23:ijms231911605. [PMID: 36232905 PMCID: PMC9570504 DOI: 10.3390/ijms231911605] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/06/2022] [Revised: 09/22/2022] [Accepted: 09/23/2022] [Indexed: 11/09/2022] Open
Abstract
Lens gap junctions (GJs) formed by Cx46 and Cx50 are important to keep lens transparency. Functional studies on Cx46 and Cx50 GJs showed that the Vj-gating, single channel conductance (γj), gating polarity, and/or channel open stability could be modified by the charged residues in the amino terminal (NT) domain. The role of hydrophobic residues in the NT on GJ properties is not clear. Crystal and cryo-EM GJ structures have been resolved, but the NT domain structure has either not been resolved or has showed very different orientations depending on the component connexins and possibly other experimental conditions, making it difficult to understand the structural basis of the NT in Vj-gating and γj. Here, we generated missense variants in Cx46 and Cx50 NT domains and studied their properties by recombinant expression and dual whole-cell patch clamp experiments on connexin-deficient N2A cells. The NT variants (Cx46 L10I, N13E, A14V, Q15N, and Cx50 I10L, E13N, V14A, N15Q) were all able to form functional GJs with similar coupling%, except Cx46 N13E, which showed a significantly reduced coupling%. The GJs of Cx46 N13E, A14V and Cx50 E13N, N15Q showed a reduced coupling conductance. Vj-gating of all the variant GJs were similar to the corresponding wild-type GJs except Cx46 L10I. The γj of Cx46 N13E, A14V, Cx50 E13N, and N15Q GJs was reduced to 51%, 82%, 87%, and 74%, respectively, as compared to their wild-type γjs. Structural models of Cx46 L10I and A14V predicted steric clashes between these residues and the TM2 residues, which might be partially responsible for our observed changes in GJ properties. To verify the importance of hydrophobic interactions, we generated a variant, Cx50 S89T, which also shows a steric clash and failed to form a functional GJ. Our experimental results and structure models indicate that hydrophobic interactions between the NT and TM2 domain are important for their Vj-gating, γj, and channel open stability in these and possibly other GJs.
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Jin A, Zhao Q, Liu S, Jin ZB, Li S, Xiang M, Zeng M, Jin K. Identification of a New Mutation p.P88L in Connexin 50 Associated with Dominant Congenital Cataract. Front Cell Dev Biol 2022; 10:794837. [PMID: 35531093 PMCID: PMC9068895 DOI: 10.3389/fcell.2022.794837] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/14/2021] [Accepted: 03/29/2022] [Indexed: 11/13/2022] Open
Abstract
Congenital hereditary cataract is genetically heterogeneous and the leading cause of visual impairment in children. Identification of hereditary causes is critical to genetic counselling and family planning. Here, we examined a four-generation Chinese pedigree with congenital dominant cataract and identified a new mutation in GJA8 via targeted exome sequencing. A heterozygous missense mutation c.263C > T, leading to a proline-to-Leucine conversion at the conserved residue 88 in the second transmembrane domain of human connexin 50 (Cx50), was identified in all patients but not in unaffected family members. Functional analyses of the mutation revealed that it disrupted the stability of Cx50 and had a deleterious effect on protein function. Indeed, the mutation compromised normal membrane permeability and gating of ions, and impeded cell migration when overexpressed. Together, our results expand the pathogenic mutation spectrum of Cx50 underlying congenital cataract and lend more support to clinical diagnosis and genetic counseling.
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Affiliation(s)
- Aixia Jin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Qingqing Zhao
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Shuting Liu
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
| | - Zi-bing Jin
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Science Key Laboratory, Beijing, China
| | - Shuyan Li
- Department of Biochemistry and Biophysics, Peking University Health Science Center, Beijing, China
| | - Mengqing Xiang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- *Correspondence: Kangxin Jin, ; Mengqing Xiang, ; Mingbing Zeng,
| | - Mingbing Zeng
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Hainan Eye Hospital, Hainan Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Haikou, China
- *Correspondence: Kangxin Jin, ; Mengqing Xiang, ; Mingbing Zeng,
| | - Kangxin Jin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-Sen University, Guangdong Provincial Key Laboratory of Ophthalmology and Visual Science, Guangzhou, China
- Beijing Institute of Ophthalmology, Beijing Tongren Eye Center, Beijing Tongren Hospital, Capital Medical University, Beijing Ophthalmology and Visual Science Key Laboratory, Beijing, China
- *Correspondence: Kangxin Jin, ; Mengqing Xiang, ; Mingbing Zeng,
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A Novel Mutation in CRYGC Mutation Associated with Autosomal Dominant Congenital Cataracts and Microcornea. OPHTHALMOLOGY SCIENCE 2022; 2:100093. [PMID: 36246175 PMCID: PMC9560566 DOI: 10.1016/j.xops.2021.100093] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/27/2021] [Revised: 12/07/2021] [Accepted: 12/13/2021] [Indexed: 11/22/2022]
Abstract
Purpose Crystallin protein mutations are associated with congenital cataract (CC), and several disease-causing mutations in the CRYGC gene have been identified. We present the location of a new mutation in CRYGC in members of a Chinese family who presented with CCs with or without microcornea. Design Observational study. Participants A Chinese family diagnosed with autosomal dominant (AD) CCs with or without microphthalmia. Methods Because this was an observational study, it was not registered as a clinical trial. The proband and her 2 children were diagnosed with AD CCs and microcornea and were recruited for the study. Participants underwent complete ophthalmological examinations, and blood samples were used for genomic extraction. Main Outcome Measures We detected 1 disease-associated variant using Exomiser analysis by matching the proband’s phenotype and the inheritance pattern. The variant was determined to be pathogenic according to American College of Medical Genetics and Genomics (ACMG) guidelines. Results We detected 1 disease-associated variant using Exomiser analysis by matching the proband’s phenotype and the inheritance pattern. The variant was determined to be pathogenic according to the American College of Medical Genetics and Genomics guidelines. Next-generation sequencing was verified using Sanger sequencing, and we confirmed that the proband and her children carried the same mutation. We identified the heterozygous variant c.389_390insGCTG (p.C130fs), which includes a frameshift mutation. The residues in p.C130fs are all highly conserved across species. This disease-causing frameshift mutation in the CRYGC gene is not currently present in the ClinVar database. Conclusions Our findings expand the repertoire of known mutations in the CRYGC gene that cause CCs and provide new insights into the etiology and molecular diagnosis of CCs; however, the molecular mechanism of this mutation warrants further investigation.
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Vanita V, Goyal S, Tibrewal S, Ganesh S. Molecular diagnosis of autosomal dominant congenital cataract in two families from North India reveals a novel and a known variant in GJA8 and GJA3. Front Pediatr 2022; 10:1003909. [PMID: 36533234 PMCID: PMC9755747 DOI: 10.3389/fped.2022.1003909] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 11/11/2022] [Indexed: 12/05/2022] Open
Abstract
AIMS The study aims to detect the underlying genetic defect in two autosomal dominant congenital cataract (ADCC) families. METHODS A detailed family history was collected, pedigrees were drawn, and slit-lamp examination and lens photography were performed. Mutation screening was carried out in the genes for crystallins and connexins by PCR and Sanger sequencing. Ethnically matched controls were tested for the identified variants. Different bioinformatics tools were used to assess the pathogenicity of the observed variants. RESULTS In an ADCC family with total cataract, a novel change (c.166A > G) (p.Thr56Ala) in GJA8 was identified. In another ADCC family with nuclear cataract, c.134G > C (p.Trp45Ser) in GJA3 has been detected. These variants co-segregated completely in patients in their respective families and were neither observed in unaffected family members nor in ethnically matched 100 controls, excluding them as polymorphisms. CONCLUSIONS The present study identifies a novel variant c.166A > G (p.Thr56Ala) in GJA8 in an ADCC family having total cataract and a previously known mutation c.134G > C (p.Trp45Ser) in GJA3 in another ADCC family. Thr56 in GJA8 seems to be a mutation hotspot, as previously an ADCC Mauritanian family harbored a different substitution (p.Thr56Pro) at the same codon, although for a different phenotype (nuclear cataract). Similarly, Trp45 in GJA3 appears as a mutation hotspot, as p.Trp45Ser has previously been reported for nuclear cataract in a Chinese ADCC family. p.Thr56 (GJA8) and p.Trp45 (GJA3) are in the extracellular loop 1 (EL1) in their respective connexin proteins, which, along with EL2, are essential for gap junction formation, hemichannel docking, and regulating the voltage gating of the channels. Hence, residues in these regions seem crucial for maintaining eye lens transparency.
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Affiliation(s)
- Vanita Vanita
- Department of Human Genetics, Guru Nanak Dev University, Amritsar, India
| | - Shiwali Goyal
- Department of Human Genetics, Guru Nanak Dev University, Amritsar, India
| | - Shailja Tibrewal
- Department of Pediatric Ophthalmology, Strabismus and Neuro-Ophthalmology, Dr. Shroff's Charity Eye Hospital, Daryaganj, India.,Department of Ocular Genetics, Dr. Shroff's Charity Eye Hospital, Daryaganj, India
| | - Suma Ganesh
- Department of Pediatric Ophthalmology, Strabismus and Neuro-Ophthalmology, Dr. Shroff's Charity Eye Hospital, Daryaganj, India
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12
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Yue B, Haddad BG, Khan U, Chen H, Atalla M, Zhang Z, Zuckerman DM, Reichow SL, Bai D. Connexin 46 and connexin 50 gap junction channel properties are shaped by structural and dynamic features of their N-terminal domains. J Physiol 2021; 599:3313-3335. [PMID: 33876426 PMCID: PMC8249348 DOI: 10.1113/jp281339] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2021] [Accepted: 04/12/2021] [Indexed: 01/02/2023] Open
Abstract
KEY POINTS Gap junctions formed by different connexins are expressed throughout the body and harbour unique channel properties that have not been fully defined mechanistically. Recent structural studies by cryo-electron microscopy have produced high-resolution models of the related but functionally distinct lens connexins (Cx50 and Cx46) captured in a stable open state, opening the door for structure-function comparison. Here, we conducted comparative molecular dynamics simulation and electrophysiology studies to dissect the isoform-specific differences in Cx46 and Cx50 intercellular channel function. We show that key determinants Cx46 and Cx50 gap junction channel open stability and unitary conductance are shaped by structural and dynamic features of their N-terminal domains, in particular the residue at the 9th position and differences in hydrophobic anchoring sites. The results of this study establish the open state Cx46/50 structural models as archetypes for structure-function studies targeted at elucidating the mechanism of gap junction channels and the molecular basis of disease-causing variants. ABSTRACT Connexins form intercellular communication channels, known as gap junctions (GJs), that facilitate diverse physiological roles, from long-range electrical and chemical coupling to coordinating development and nutrient exchange. GJs formed by different connexin isoforms harbour unique channel properties that have not been fully defined mechanistically. Recent structural studies on Cx46 and Cx50 defined a novel and stable open state and implicated the amino-terminal (NT) domain as a major contributor for isoform-specific functional differences between these closely related lens connexins. To better understand these differences, we constructed models corresponding to wildtype Cx50 and Cx46 GJs, NT domain swapped chimeras, and point variants at the 9th residue for comparative molecular dynamics (MD) simulation and electrophysiology studies. All constructs formed functional GJ channels, except the chimeric Cx46-50NT variant, which correlated with an introduced steric clash and increased dynamical behaviour (instability) of the NT domain observed by MD simulation. Single channel conductance correlated well with free-energy landscapes predicted by MD, but resulted in a surprisingly greater degree of effect. Additionally, we observed significant effects on transjunctional voltage-dependent gating (Vj gating) and/or open state dwell times induced by the designed NT domain variants. Together, these studies indicate intra- and inter-subunit interactions involving both hydrophobic and charged residues within the NT domains of Cx46 and Cx50 play important roles in defining GJ open state stability and single channel conductance, and establish the open state Cx46/50 structural models as archetypes for structure-function studies targeted at elucidating GJ channel mechanisms and the molecular basis of cataract-linked connexin variants.
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Affiliation(s)
- Benny Yue
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Bassam G. Haddad
- Department of Chemistry, Portland State University, Portland, OR 97201, USA
| | - Umair Khan
- Department of Chemistry, Portland State University, Portland, OR 97201, USA
| | - Honghong Chen
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Mena Atalla
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Ze Zhang
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
| | - Daniel M. Zuckerman
- Department of Biomedical Engineering, Oregon Health and Science University, Portland, OR 97239, USA
| | - Steve L. Reichow
- Department of Chemistry, Portland State University, Portland, OR 97201, USA
| | - Donglin Bai
- Department of Physiology and Pharmacology, University of Western Ontario, London, Ontario, Canada
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13
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Zhou Y, Bennett TM, Shiels A. Mutation of the TRPM3 cation channel underlies progressive cataract development and lens calcification associated with pro-fibrotic and immune cell responses. FASEB J 2021; 35:e21288. [PMID: 33484482 DOI: 10.1096/fj.202002037r] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2020] [Revised: 11/23/2020] [Accepted: 12/03/2020] [Indexed: 12/11/2022]
Abstract
Transient-receptor-potential cation channel, subfamily M, member 3 (TRPM3) serves as a polymodal calcium sensor in diverse mammalian cell-types. Mutation of the human TRPM3 gene (TRPM3) has been linked with inherited forms of early-onset cataract with or without other eye abnormalities. Here, we have characterized the ocular phenotypes of germline "knock-in" mice that harbor a human cataract-associated isoleucine-to-methionine mutation (p.I65M) in TRPM3 (Trpm3-mutant) compared with germline "knock-out" mice that functionally lack TRPM3 (Trpm3-null). Despite strong expression of Trpm3 in lens epithelial cells, neither heterozygous (Trpm3+/- ) nor homozygous (Trpm3-/- ) Trpm3-null mice developed cataract; however, the latter exhibited a mild impairment of lens growth. In contrast, homozygous Trpm3-M/M mutants developed severe, progressive, anterior pyramid-like cataract with microphthalmia, whereas heterozygous Trpm3-I/M and hemizygous Trpm3-M/- mutants developed anterior pyramidal cataract with delayed onset and progression-consistent with a semi-dominant lens phenotype. Histochemical staining revealed abnormal accumulation of calcium phosphate-like deposits and collagen fibrils in Trpm3-mutant lenses and immunoblotting detected increased αII-spectrin cleavage products consistent with calpain hyper-activation. Immunofluorescent confocal microscopy of Trpm3-M/M mutant lenses revealed fiber cell membrane degeneration that was accompanied by accumulation of alpha-smooth muscle actin positive (α-SMA+ve) myofibroblast-like cells and macrosialin positive (CD68+ve) macrophage-like cells. Collectively, our mouse model data support an ocular disease association for TRPM3 in humans and suggest that (1) Trpm3 deficiency impaired lens growth but not lens transparency and (2) Trpm3 dysfunction resulted in progressive lens degeneration and calcification coupled with pro-fibrotic (α-SMA+ve) and immune (CD68+ve) cell responses.
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Affiliation(s)
- Yuefang Zhou
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Thomas M Bennett
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
| | - Alan Shiels
- Ophthalmology and Visual Sciences, Washington University School of Medicine, St. Louis, MO, USA
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14
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Edwards SD, Schulze KV, Rosenfeld JA, Westerfield LE, Gerard A, Yuan B, Grigorenko EL, Posey JE, Bi W, Liu P. Clinical characterization of individuals with the distal 1q21.1 microdeletion. Am J Med Genet A 2021; 185:1388-1398. [PMID: 33576134 DOI: 10.1002/ajmg.a.62104] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2020] [Accepted: 01/09/2021] [Indexed: 11/12/2022]
Abstract
Distal 1q21.1 microdeletions have shown highly variable clinical expressivity and incomplete penetrance, with affected individuals manifesting a broad spectrum of nonspecific features. The goals of this study were to better describe the phenotypic spectrum of patients with distal 1q21.1 microdeletions and to compare the clinical features among affected individuals. We performed a retrospective chart review of 47 individuals with distal 1q21.1 microdeletions tested at a large clinical genetic testing laboratory, with most patients being clinically evaluated in the same children's hospital. Health information such as growth charts, results of imaging studies, developmental history, and progress notes were collected. Statistical analysis was performed using Fisher's exact test to compare clinical features among study subjects. Common features in our cohort include microcephaly (51.2%), seizures (29.8%), developmental delay (74.5%), failure to thrive (FTT) (68.1%), dysmorphic features (63.8%), and a variety of congenital anomalies such as cardiac abnormalities (23.4%) and genitourinary abnormalities (19.1%). Compared to prior literature, we found that seizures, brain anomalies, and FTT were more prevalent among our study cohort. Females were more likely than males to have microcephaly (p = 0.0199) and cardiac abnormalities (p = 0.0018). Based on existing genome-wide clinical testing results, at least a quarter of the cohort had additional genetic findings that may impact the phenotype of the individual. Our study represents the largest cohort of distal 1q21.1 microdeletion carriers available in the literature thus far, and it further illustrates the wide spectrum of clinical manifestations among symptomatic individuals. These results may allow for improved genetic counseling and management of affected individuals. Future studies may help to elucidate the underlying molecular mechanisms impacting the phenotypic variability observed with this microdeletion.
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Affiliation(s)
- Stacey D Edwards
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Katharina V Schulze
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Jill A Rosenfeld
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Lauren E Westerfield
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Texas Children's Hospital, Houston, Texas, USA
| | - Amanda Gerard
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Texas Children's Hospital, Houston, Texas, USA
| | - Bo Yuan
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Baylor Genetics, Houston, Texas, USA
| | - Elena L Grigorenko
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,St. Petersburg State University, St Petersburg, Russia
| | - Jennifer E Posey
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA
| | - Weimin Bi
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Baylor Genetics, Houston, Texas, USA
| | - Pengfei Liu
- Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, Texas, USA.,Baylor Genetics, Houston, Texas, USA
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15
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Mesnil M, Defamie N, Naus C, Sarrouilhe D. Brain Disorders and Chemical Pollutants: A Gap Junction Link? Biomolecules 2020; 11:biom11010051. [PMID: 33396565 PMCID: PMC7824109 DOI: 10.3390/biom11010051] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 12/22/2020] [Accepted: 12/23/2020] [Indexed: 02/07/2023] Open
Abstract
The incidence of brain pathologies has increased during last decades. Better diagnosis (autism spectrum disorders) and longer life expectancy (Parkinson's disease, Alzheimer's disease) partly explain this increase, while emerging data suggest pollutant exposures as a possible but still underestimated cause of major brain disorders. Taking into account that the brain parenchyma is rich in gap junctions and that most pollutants inhibit their function; brain disorders might be the consequence of gap-junctional alterations due to long-term exposures to pollutants. In this article, this hypothesis is addressed through three complementary aspects: (1) the gap-junctional organization and connexin expression in brain parenchyma and their function; (2) the effect of major pollutants (pesticides, bisphenol A, phthalates, heavy metals, airborne particles, etc.) on gap-junctional and connexin functions; (3) a description of the major brain disorders categorized as neurodevelopmental (autism spectrum disorders, attention deficit hyperactivity disorders, epilepsy), neurobehavioral (migraines, major depressive disorders), neurodegenerative (Parkinson's and Alzheimer's diseases) and cancers (glioma), in which both connexin dysfunction and pollutant involvement have been described. Based on these different aspects, the possible involvement of pollutant-inhibited gap junctions in brain disorders is discussed for prenatal and postnatal exposures.
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Affiliation(s)
- Marc Mesnil
- Laboratoire STIM, ERL7003 CNRS-Université de Poitiers, 1 rue G. Bonnet–TSA 51 106, 86073 Poitiers, France; (M.M.); (N.D.)
| | - Norah Defamie
- Laboratoire STIM, ERL7003 CNRS-Université de Poitiers, 1 rue G. Bonnet–TSA 51 106, 86073 Poitiers, France; (M.M.); (N.D.)
| | - Christian Naus
- Faculty of Medicine, Department of Cellular & Physiological Sciences, Life Sciences Institute, University of British Columbia, 2350 Health Sciences Mall, Vancouver, BC V6T1Z3, Canada;
| | - Denis Sarrouilhe
- Laboratoire de Physiologie Humaine, Faculté de Médecine et Pharmacie, 6 rue de La Milétrie, bât D1, TSA 51115, 86073 Poitiers, France
- Correspondence: ; Tel.: +33-5-49-45-43-58
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16
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Taylan Sekeroglu H, Karaosmanoglu B, Taskiran EZ, Simsek Kiper PO, Alikasifoglu M, Boduroglu K, Coskun T, Utine GE. Molecular Etiology of Isolated Congenital Cataract Using Next-Generation Sequencing: Single Center Exome Sequencing Data from Turkey. Mol Syndromol 2020; 11:302-308. [PMID: 33510601 DOI: 10.1159/000510481] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Accepted: 07/26/2020] [Indexed: 12/31/2022] Open
Abstract
Congenital cataract, which refers to lenticular opacity diagnosed at birth or more commonly during the first year of life, is one of the leading causes of childhood blindness. Molecular understanding of the disease pathogenesis has evolved thanks to many studies based on modern technologies. In this study, we aimed to identify and discuss the molecular etiology of nonsyndromic or nonmetabolic bilateral congenital cataract by whole-exome sequencing (WES). Patients with bilateral congenital cataract presumed to be isolated after metabolic and genetic evaluation were enrolled in the study. All patients underwent detailed ophthalmological examination and bilateral cataract surgery. DNA samples of the probands, parents, and available affected family members were analyzed by WES. Variants were validated and confirmed by Sanger sequencing in all probands and in available affected family members. A total of 4 patients (3 girls and 1 boy) were recruited. Two patients had nuclear, 1 patient had total, and 1 patient had combined lamellar and sutural cataract. One family had consanguinity. A heterozygous c.215+1G>A mutation in CRYBA1, heterozygous c.432C>G (p.Tyr144Ter) mutation in CRYGC, heterozygous c.70A>C (p.Pro24Thr) mutation in CRYGD, and a heterozygous c.466G>A (p.Gly156Arg) mutation in CRYBB3 were detected. All these mutations were confirmed by Sanger sequencing in selected affected individuals. The current study identified all causative mutations of congenital cataract in the crystalline genes. The results confirmed that WES is a very useful tool in the investigation of the diseases with heterogeneous genetic background.
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Affiliation(s)
| | - Beren Karaosmanoglu
- Department of Medical Genetics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Ekim Z Taskiran
- Department of Medical Genetics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Pelin O Simsek Kiper
- Division of Pediatric Genetics, Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Mehmet Alikasifoglu
- Department of Medical Genetics, Hacettepe University Faculty of Medicine, Ankara, Turkey.,Division of Pediatric Genetics, Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Koray Boduroglu
- Department of Medical Genetics, Hacettepe University Faculty of Medicine, Ankara, Turkey.,Division of Pediatric Genetics, Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Turgay Coskun
- Division of Metabolism, Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey
| | - Gulen Eda Utine
- Division of Pediatric Genetics, Department of Pediatrics, Hacettepe University Faculty of Medicine, Ankara, Turkey
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17
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Fan F, Luo Y, Wu J, Gao C, Liu X, Mei H, Zhou X. The mutation spectrum in familial versus sporadic congenital cataract based on next-generation sequencing. BMC Ophthalmol 2020; 20:361. [PMID: 32883240 PMCID: PMC7469093 DOI: 10.1186/s12886-020-01567-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2020] [Accepted: 07/13/2020] [Indexed: 12/20/2022] Open
Abstract
BACKGROUND Congenital cataract (CC) is a significant cause of lifelong visual loss, and its genetic diagnosis is challenging due to marked genetic heterogeneity. The purpose of this article is to report the genetic findings in sporadic and familial CC patients. METHODS Patients (n = 53) who were clinically diagnosed with CC and their parents were recruited. Blood samples were collected in our hospital. Mutations were detected by panel-based next-generation DNA sequencing (NGS) targeting 792 genes frequently involved in common inherited eye diseases. RESULTS We identified variants in 10/37 cases (27.02%) of sporadic CC and 14/16 cases (87.5%) of familial CC, which indicated a significant difference (P = 0.000). Of the 13 variants identified in sporadic cases, nine were previously reported mutations, and three were novel mutations, including one de novo mutation (CRYBB2 c.487C > T). The most frequent variants in our cohort were in crystallins and cytoskeletal genes (5/27, 18.52%), followed by proteins associated with X-linked syndromic conditions (14.81%) and transcriptional factors (11.11%). Additional information on the possibility of complications with inherited ocular or systemic diseases other than CC was provided in 17/27 (62.96%) variants. CONCLUSIONS These results contribute to expanding the mutation spectrum and frequency of genes responsible for CC. Targeted NGS in CC provided significant diagnostic information and enabled more accurate genetic counselling. This study reports the different distributions of mutation genes in familial and sporadic CC cases.
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Affiliation(s)
- Fan Fan
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Eye Institute, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Yi Luo
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China. .,Eye Institute, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China. .,Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China.
| | - Jihong Wu
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Eye Institute, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Chao Gao
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Eye Institute, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Xin Liu
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Eye Institute, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Hengjun Mei
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Eye Institute, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
| | - Xiyue Zhou
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Eye Institute, Eye and Ear, Nose, and Throat Hospital, Fudan University, Shanghai, China.,Key Laboratory of Myopia, Chinese Academy of Medical Sciences, Shanghai, China
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18
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Vujkovic M, Keaton JM, Lynch JA, Miller DR, Zhou J, Tcheandjieu C, Huffman JE, Assimes TL, Lorenz K, Zhu X, Hilliard AT, Judy RL, Huang J, Lee KM, Klarin D, Pyarajan S, Danesh J, Melander O, Rasheed A, Mallick NH, Hameed S, Qureshi IH, Afzal MN, Malik U, Jalal A, Abbas S, Sheng X, Gao L, Kaestner KH, Susztak K, Sun YV, DuVall SL, Cho K, Lee JS, Gaziano JM, Phillips LS, Meigs JB, Reaven PD, Wilson PW, Edwards TL, Rader DJ, Damrauer SM, O'Donnell CJ, Tsao PS, Chang KM, Voight BF, Saleheen D. Discovery of 318 new risk loci for type 2 diabetes and related vascular outcomes among 1.4 million participants in a multi-ancestry meta-analysis. Nat Genet 2020; 52:680-691. [PMID: 32541925 PMCID: PMC7343592 DOI: 10.1038/s41588-020-0637-y] [Citation(s) in RCA: 373] [Impact Index Per Article: 93.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Accepted: 04/29/2020] [Indexed: 12/19/2022]
Abstract
We investigated type 2 diabetes (T2D) genetic susceptibility via multi-ethnic meta-analysis of 228,499 cases and 1,178,783 controls in the Million Veteran Program, DIAMANTE, Biobank Japan, and other studies. We report 568 associations, including 286 autosomal, 7 X chromosomal, and 25 identified in ancestry-specific analyses that were previously unreported. Transcriptome-wide association analysis detected 3,568 T2D-associations with genetically predicted gene expression in 687 novel genes; of these, 54 are known to interact with FDA-approved drugs. A polygenic risk score was strongly associated with increased risk of T2D-related retinopathy and modestly associated with chronic kidney disease (CKD), peripheral artery disease (PAD), and neuropathy. We investigated the genetic etiology of T2D-related vascular outcomes in MVP and observed statistical SNP-T2D interactions at 13 variants, including coronary heart disease, CKD, PAD, and neuropathy. These findings may help to identify potential therapeutic targets for T2D and genomic pathways that link T2D to vascular outcomes.
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Affiliation(s)
- Marijana Vujkovic
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA.,Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Jacob M Keaton
- Biomedical Laboratory Research and Development, Tennessee Valley Healthcare System, Nashville, TN, USA.,Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Medicine, Vanderbilt University Medical Center, Nashville, TN, USA.,Department of Biomedical Informatics, Vanderbilt University Medical Center, Nashville, TN, USA
| | - Julie A Lynch
- VA Informatics and Computing Infrastructure, VA Salt Lake City Health Care System, Salt Lake City, UT, USA.,College of Nursing and Health Sciences, University of Massachusetts, Lowell, MA, USA
| | - Donald R Miller
- Edith Nourse Rogers Memorial VA Hospital, Bedford, MA, USA.,Center for Population Health, University of Massachusetts, Lowell, MA, USA
| | - Jin Zhou
- Phoenix VA Health Care System, Phoenix, AZ, USA.,Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ, USA
| | - Catherine Tcheandjieu
- VA Palo Alto Health Care System, Palo Alto, CA, USA.,Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA.,Department of Pediatric Cardiology, Stanford University School of Medicine, Stanford, CA, USA
| | | | - Themistocles L Assimes
- VA Palo Alto Health Care System, Palo Alto, CA, USA.,Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Kimberly Lorenz
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA.,Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.,Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Xiang Zhu
- VA Palo Alto Health Care System, Palo Alto, CA, USA.,Department of Statistics, Stanford University, Stanford, CA, USA
| | - Austin T Hilliard
- VA Palo Alto Health Care System, Palo Alto, CA, USA.,Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - Renae L Judy
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA.,Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Jie Huang
- VA Boston Healthcare System, Boston, MA, USA.,Department of Global Health, Peking University School of Public Health, Beijing, China
| | - Kyung M Lee
- VA Informatics and Computing Infrastructure, VA Salt Lake City Health Care System, Salt Lake City, UT, USA
| | - Derek Klarin
- VA Boston Healthcare System, Boston, MA, USA.,Center for Genomic Medicine, Massachusetts General Hospital, Boston, MA, USA.,Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Division of Vascular Surgery and Endovascular Therapy, University of Florida School of Medicine, Gainesville, FL, USA
| | - Saiju Pyarajan
- VA Boston Healthcare System, Boston, MA, USA.,Department of Medicine, Brigham Women's Hospital, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - John Danesh
- Department of Public Health and Primary Care, University of Cambridge, Cambridge, UK
| | - Olle Melander
- Department of Clinical Sciences Malmö, Lund University, Malmö, Sweden
| | - Asif Rasheed
- Center for Non-Communicable Diseases, Karachi, Sindh, Pakistan
| | | | - Shahid Hameed
- Punjab Institute of Cardiology, Lahore, Punjab, Pakistan
| | - Irshad H Qureshi
- Department of Medicine, King Edward Medical University, Lahore, Punjab, Pakistan.,Mayo Hospital, Lahore, Punjab, Pakistan
| | - Muhammad Naeem Afzal
- Department of Medicine, King Edward Medical University, Lahore, Punjab, Pakistan.,Mayo Hospital, Lahore, Punjab, Pakistan
| | - Uzma Malik
- Department of Medicine, King Edward Medical University, Lahore, Punjab, Pakistan.,Mayo Hospital, Lahore, Punjab, Pakistan
| | - Anjum Jalal
- Department of Cardiology, Faisalabad Institute of Cardiology, Faisalabad, Punjab, Pakistan
| | - Shahid Abbas
- Department of Cardiology, Faisalabad Institute of Cardiology, Faisalabad, Punjab, Pakistan
| | - Xin Sheng
- Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Long Gao
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Klaus H Kaestner
- Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Katalin Susztak
- Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Yan V Sun
- Atlanta VA Medical Center, Decatur, GA, USA.,Department of Epidemiology, Emory University Rollins School of Public Health, Atlanta, GA, USA
| | - Scott L DuVall
- VA Informatics and Computing Infrastructure, VA Salt Lake City Health Care System, Salt Lake City, UT, USA.,Department of Internal Medicine, University of Utah School of Medicine, Salt Lake City, UT, USA
| | - Kelly Cho
- VA Boston Healthcare System, Boston, MA, USA.,Department of Medicine, Brigham Women's Hospital, Boston, MA, USA
| | - Jennifer S Lee
- VA Palo Alto Health Care System, Palo Alto, CA, USA.,Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | - J Michael Gaziano
- VA Boston Healthcare System, Boston, MA, USA.,Department of Medicine, Brigham Women's Hospital, Boston, MA, USA
| | - Lawrence S Phillips
- Atlanta VA Medical Center, Decatur, GA, USA.,Division of Endocrinology, Emory University School of Medicine, Atlanta, GA, USA
| | - James B Meigs
- Program in Medical and Population Genetics, Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA.,Division of General Internal Medicine, Massachusetts General Hospital, Boston, MA, USA
| | - Peter D Reaven
- Phoenix VA Health Care System, Phoenix, AZ, USA.,College of Medicine, University of Arizona, Phoenix, AZ, USA
| | - Peter W Wilson
- Atlanta VA Medical Center, Decatur, GA, USA.,Division of Cardiology, Emory University School of Medicine, Atlanta, GA, USA
| | - Todd L Edwards
- Vanderbilt Genetics Institute, Vanderbilt University Medical Center, Nashville, TN, USA.,Nashville VA Medical Center, Nashville, TN, USA
| | - Daniel J Rader
- Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.,Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Scott M Damrauer
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA.,Department of Surgery, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA
| | - Christopher J O'Donnell
- VA Boston Healthcare System, Boston, MA, USA.,Department of Medicine, Brigham Women's Hospital, Boston, MA, USA.,Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Philip S Tsao
- VA Palo Alto Health Care System, Palo Alto, CA, USA.,Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
| | | | | | | | - Kyong-Mi Chang
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA.,Department of Medicine, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.,South Texas Veterans Health Care System, San Antonio, TX, USA
| | - Benjamin F Voight
- Corporal Michael J. Crescenz VA Medical Center, Philadelphia, PA, USA. .,Department of Genetics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA. .,Department of Systems Pharmacology and Translational Therapeutics, University of Pennsylvania Perelman School of Medicine, Philadelphia, PA, USA.
| | - Danish Saleheen
- Center for Non-Communicable Diseases, Karachi, Sindh, Pakistan. .,Department of Medicine, Columbia University Irving Medical Center, New York, NY, USA. .,Department of Cardiology, Columbia University Irving Medical Center, New York, NY, USA.
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19
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Two Pathogenic Gene Mutations Identified Associating with Congenital Cataract and Iris Coloboma Respectively in a Chinese Family. J Ophthalmol 2020; 2020:7054315. [PMID: 32148946 PMCID: PMC7049832 DOI: 10.1155/2020/7054315] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2019] [Accepted: 12/26/2019] [Indexed: 12/13/2022] Open
Abstract
Purpose To screen out pathogenic genes in a Chinese family with congenital cataract and iris coloboma. Material and Methods. A three-generation family with congenital cataract and iris coloboma from a Han ethnicity was recruited. DNA was extracted from peripheral blood samples collected from all individuals in the family. Whole exon sequencing was employed for screening the disease-causing gene mutations in the proband, and Sanger sequencing was used for other members of the family and a control group of 500 healthy individuals. Bioinformatics analysis and three-dimensional structure predictions were used to predict the impact of amino acid changes on protein structure and function. Results The candidate genes of cataract and iris coloboma were successfully screened out. A heterozygote mutation, CRYGD c.70C>A (p.P24T), was identified as cosegregating with congenital cataracts, while another heterozygous mutation, WFS1 c.1514G>C (p.C505S), which had not been reported previously, cosegregated with congenital iris coloboma. Bioinformatic analyses and three-dimensional structure prediction proved that the three-dimensional structures of WFS1 c.1514G>C (p.C505S), which had not been reported previously, cosegregated with congenital iris coloboma. Bioinformatic analyses and three-dimensional structure prediction proved that the three-dimensional structures of CRYGD c.70C>A (p.P24T), was identified as cosegregating with congenital cataracts, while another heterozygous mutation, Conclusions We report a novel mutation, WFS1 p.C505S, and a known mutation, CRYGD p.P24T, that cosegregate with iris coloboma and congenital cataract, respectively, in a Chinese family. This is the first time the association of WFS1 p.C505S with iris coloboma has been demonstrated, although CRYGD p.P24T has been widely reported as being associated with congenital cataract, especially in the Eastern Asian population. These findings may have future therapeutic benefit for the diagnosis of iris coloboma and congenital cataract. The results may also be relevant in further studies aiming to investigate the molecular pathogenesis of iris coloboma and congenital cataract.WFS1 c.1514G>C (p.C505S), which had not been reported previously, cosegregated with congenital iris coloboma. Bioinformatic analyses and three-dimensional structure prediction proved that the three-dimensional structures of CRYGD c.70C>A (p.P24T), was identified as cosegregating with congenital cataracts, while another heterozygous mutation, WFS1 c.1514G>C (p.C505S), which had not been reported previously, cosegregated with congenital iris coloboma. Bioinformatic analyses and three-dimensional structure prediction proved that the three-dimensional structures of CRYGD c.70C>A (p.P24T), was identified as cosegregating with congenital cataracts, while another heterozygous mutation,
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20
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Li S, Zhang J, Cao Y, You Y, Zhao X. Novel mutations identified in Chinese families with autosomal dominant congenital cataracts by targeted next-generation sequencing. BMC MEDICAL GENETICS 2019; 20:196. [PMID: 31842807 PMCID: PMC6915918 DOI: 10.1186/s12881-019-0933-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/14/2019] [Accepted: 12/01/2019] [Indexed: 11/18/2022]
Abstract
Background Congenital cataract is a clinically and genetically heterogeneous visual impairment. The aim of this study was to identify causative mutations in five unrelated Chinese families diagnosed with congenital cataracts. Methods Detailed family history and clinical data were collected, and ophthalmological examinations were performed using slit-lamp photography. Genomic DNA was extracted from peripheral blood of all available members. Thirty-eight genes associated with cataract were captured and sequenced in 5 typical nonsyndromic congenital cataract probands by targeted next-generation sequencing (NGS), and the results were confirmed by Sanger sequencing. Bioinformatics analysis was performed to predict the functional effect of mutant genes. Results Results from the DNA sequencing revealed five potential causative mutations: c.154 T > C(p.F52 L) in GJA8 of Family 1, c.1152_1153insG(p.S385Efs*83) in GJA3 of Family 2, c.1804 G > C(p.G602R) in BFSP1 of Family 3, c.1532C > T(p.T511 M) in EPHA2 of Family 4 and c.356G > A(p.R119H) in HSF4 of Family 5. These mutations co-segregated with all affected individuals in the families and were not found in unaffected family members nor in 50 controls. Bioinformatics analysis from several prediction tools supported the possible pathogenicity of these mutations. Conclusions In this study, we identified five novel mutations (c.154 T > C in GJA8, c.1152_1153insG in GJA3, c.1804G > C in BFSP1, c.1532C > T in EPHA2, c.356G > A in HSF4) in five Chinese families with hereditary cataracts, respectively. NGS can be used as an effective tool for molecular diagnosis of genetically heterogeneous disorders such as congenital cataract, and the results can provide more effective clinical diagnosis and genetic counseling for the five families.
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Affiliation(s)
- Shan Li
- Department of Medical Genetics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences - School of Basic Medicine Peking Union Medical College, 5 Dong Dan San Tiao, Dongcheng District, Beijing, 100005, People's Republic of China
| | - Jianfei Zhang
- The No.4 hospital (eye hospital) of Zhangjiakou, Zhangjiakou, 075000, People's Republic of China
| | - Yixuan Cao
- Department of Medical Genetics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences - School of Basic Medicine Peking Union Medical College, 5 Dong Dan San Tiao, Dongcheng District, Beijing, 100005, People's Republic of China
| | - Yi You
- Department of Medical Genetics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences - School of Basic Medicine Peking Union Medical College, 5 Dong Dan San Tiao, Dongcheng District, Beijing, 100005, People's Republic of China
| | - Xiuli Zhao
- Department of Medical Genetics, Institute of Basic Medical Sciences Chinese Academy of Medical Sciences - School of Basic Medicine Peking Union Medical College, 5 Dong Dan San Tiao, Dongcheng District, Beijing, 100005, People's Republic of China.
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21
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Molecular genetics of congenital cataracts. Exp Eye Res 2019; 191:107872. [PMID: 31770519 DOI: 10.1016/j.exer.2019.107872] [Citation(s) in RCA: 53] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2019] [Revised: 11/12/2019] [Accepted: 11/13/2019] [Indexed: 12/18/2022]
Abstract
Congenital cataracts, the most common cause of visual impairment and blindness in children worldwide, have diverse etiologies. According to statistics analysis, about one quarter of congenital cataracts caused by genetic defects. Various mutations of more than one hundred genes have been identified in hereditary cataracts so far. In this review, we briefly summarize recent developments about the genetics, molecular mechanisms, and treatments of congenital cataracts. The studies of these pathogenic mutations and molecular genetics is making it possible for us to comprehend the underlying mechanisms of cataractogenesis and providing new insights into the preventive, diagnostic and therapeutic approaches of cataracts.
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22
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Ye Y, Wu M, Qiao Y, Xie T, Yu Y, Yao K. Identification and preliminary functional analysis of two novel congenital cataract associated mutations of Cx46 and Cx50. Ophthalmic Genet 2019; 40:428-435. [PMID: 31618082 DOI: 10.1080/13816810.2019.1675179] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 09/10/2019] [Accepted: 09/25/2019] [Indexed: 01/24/2023]
Abstract
Background: Congenital cataract is a significant cause of visual impairment and blindness. The present study examined the disease-causing mutations in three Chinese families with autosomal dominant congenital cataract (ADCC) to provide the preliminary evidence of the mechanisms underlying congenital cataract formation.Methods: Three pedigrees affected with ADCC were recruited. All participants underwent detailed ophthalmic examinations. Leucocyte DNA was extracted from venous blood for direct sequencing of candidate genes. In silico bioinformatics analysis was conducted to verify the functional impacts of the mutant proteins. Distribution patterns of connexin proteins were assessed through fluorescence microscopy using an enhanced green fluorescent protein (EGFP)-labeled expression vector in stably transfected Hek293 cells.Results: We identified three Chinese pedigrees with ADCC. Family 1 and family 2 presented with pulverized cataract and family 3 with an unknown phenotype. Direct sequencing of family 1 and family 2 revealed a missense mutation of c.64G>A encoding for G22S of connexin46 (Cx46), while a similar c.64G>A encoding for G22S of connexin50 (Cx50) was found in family 3; both mutations co-segregated well within all affected individuals in their families and were absent from 100 unrelated controls. Bioinformatics analysis revealed with high confidence that both mutations were deleterious. Confocal microscopy revealed the accumulation of both mutant connexins in the cytoplasm with punctate staining and a failure of gap junction formation between adjacent cells.Conclusions: Two novel G22S mutations of Cx46 and Cx50 were identified, and preliminary functional analysis revealed a potential deleterious effect of these mutations due to the malfunction of connexins.Abbreviations: ADCC: autosomal dominant congenital cataract; Cx26: connexin26; Cx32: connexin32; Cx46: connexin46; Cx46WT: wild-type connexin46; Cx50: Connexin50; Cx50WT: wild-type connexin50; DAPI: 4',6-diamidino-2-phenylindole; EGFP: enhanced green fluorescent protein; FBS: fetal bovine serum; GJA-:gap junction alpha-; PCR: polymerase chain reaction; PolyPhen: polymorphism phenotyping; PSIC: position-specific independent count; RPMI: Roswell Park Memorial Institute; TM1: first transmembrane.
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Affiliation(s)
- Yang Ye
- Department of Eye Center, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, China
| | - Menghan Wu
- Intensive Care Unit, Zhejiang Hospital, Hangzhou, China
| | - Yue Qiao
- Institute of Translational Medicine, Zhejiang University, Hangzhou, China
| | - Tingting Xie
- Institute of Translational Medicine, Zhejiang University, Hangzhou, China
| | - Yinhui Yu
- Department of Eye Center, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, China
| | - Ke Yao
- Department of Eye Center, Second Affiliated Hospital of Zhejiang University School of Medicine, Hangzhou, China
- Zhejiang Provincial Key Lab of Ophthalmology, Hangzhou, China
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23
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Hadrami M, Bonnet C, Veten F, Zeitz C, Condroyer C, Wang P, Biya M, Sidi Ahmed MA, Zhang Q, Cheikh S, Audo I, Petit C, Houmeida A. A novel missense mutation of GJA8 causes congenital cataract in a large Mauritanian family. Eur J Ophthalmol 2018; 29:621-628. [PMID: 30373400 DOI: 10.1177/1120672118804757] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
OBJECTIVE OF THE STUDY Inborn lens opacity is the most frequent cause of childhood blindness. In this study, we aimed to define the presumed genetic cause of a congenital cataract present in a Mauritanian family over the last nine generations. METHODS A family history of the disease and eye examination were carried out for the family members. Next-generation sequencing using a panel of 116 cataract underlying genes was selectively conducted on the proband's DNA. Nucleotide and amino acid changes and their impact on the phenotype were evaluated using various data analyzing software. RESULTS Congenital nuclear cataract, with autosomal dominant mode, was observed in the family. All patients had consequences on their vision in the first 2 years of life. Genetic screening revealed a new mutation c.166A>C (p.Thr56Pro) in GJA8, encoding the Cx50 α-connexin protein. This mutation co-segregated in all patients and was not observed in the unaffected family members and controls. The predicted secondary structure impacted by p.Thr56Pro revealed a localized disruption, in the first extra membrane loop of the wild-type sheet, which is replaced in the mutant protein by a turn then a coil. This conformational change was functionally predicted as probably damaging. CONCLUSION A new mutation (c.166A>C) in GJA8 underlying a nuclear congenital cataract was identified in this study. Its segregation with the phenotype might be useful as a predicting marker of the disease.
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Affiliation(s)
- Mouna Hadrami
- Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritanie
| | - Crystel Bonnet
- Syndrome de Usher et Autres Atteintes Rétino-Cochléaires, Institut de la Vision, Paris, France.,UMRS 1120, Institut National de la Santé et de la Recherche Médicale, Paris, France.,Complexité du Vivant, UPMC Université Paris 06, Sorbonne Universités, Paris, France
| | - Fatimetou Veten
- Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritanie
| | - Christina Zeitz
- Institut de la Vision, CNRS-INSERM, Sorbonne Université, Paris, France
| | | | - Panfeng Wang
- Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Mohamed Biya
- Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritanie
| | | | - Qingjiong Zhang
- Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Sidi Cheikh
- Service Ophtalmologie, Centre Hospitalier National, Nouakchott, Mauritanie
| | - Isabelle Audo
- Institut de la Vision, CNRS-INSERM, Sorbonne Université, Paris, France.,Centre Hospitalier National d'Ophtalmologie des Quinze-Vingts, DHU Sight Restore, INSERM-DHOS CIC 1423, Paris, France.,Institute of Ophthalmology, University College of London, London, UK
| | - Christine Petit
- Syndrome de Usher et Autres Atteintes Rétino-Cochléaires, Institut de la Vision, Paris, France.,UMRS 1120, Institut National de la Santé et de la Recherche Médicale, Paris, France.,Complexité du Vivant, UPMC Université Paris 06, Sorbonne Universités, Paris, France.,Unité de Génétique et Physiologie de l'Audition, Institut Pasteur, Paris, France.,Collège de France, Paris, France
| | - Ahmed Houmeida
- Unité de Recherche sur les Biomarqueurs dans la Population Mauritanienne, Université des Sciences de Technologies et de médecine (USTM), Nouakchott, Mauritanie
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24
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Yu X, Ping X, Zhang X, Cui Y, Yang H, Tang X, Tang Y, Shentu X. The impact of GJA8 SNPs on susceptibility to age-related cataract. Hum Genet 2018; 137:897-904. [PMID: 30349978 PMCID: PMC6267713 DOI: 10.1007/s00439-018-1945-5] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2018] [Accepted: 10/12/2018] [Indexed: 12/05/2022]
Abstract
The gap junction protein alpha 8 (GJA8) gene has been widely studied in human congenital cataracts. However, little is known about its relationship with age-related cataract (ARC). In this study, three GJA8-tagged single nucleotide polymorphisms related to an increased ARC risk were identified: rs2132397 for general ARC under both dominant and additive models; rs7541950 for general ARC under both recessive and additive models; and rs6657114 for cortical cataract under the recessive model. To uncover the underlying mechanisms, this study also sought to explore whether GJA8 is involved in the autophagy process in human lens epithelial cells. The results showed that GJA8 may participate in autophagy to maintain the intracellular environment, which may be a novel mechanism for cataract formation induced by GJA8. In conclusion, this study identified the genetic susceptibility of GJA8 polymorphisms on ARC and provides new clues for fully understanding the pathological mechanism of GJA8 variants in affecting lens opacity.
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Affiliation(s)
- Xiaoning Yu
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Xiyuan Ping
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Xin Zhang
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Yilei Cui
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Hao Yang
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Xiajing Tang
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Yelei Tang
- The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China
| | - Xingchao Shentu
- Eye Center, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, 310009, Zhejiang, China.
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25
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Chen P, Chen H, Pan XJ, Tang SZ, Xia YJ, Zhang H. Novel mutations in CRYBB1/CRYBB2 identified by targeted exome sequencing in Chinese families with congenital cataract. Int J Ophthalmol 2018; 11:1577-1582. [PMID: 30364188 PMCID: PMC6192965 DOI: 10.18240/ijo.2018.10.01] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2017] [Accepted: 05/08/2018] [Indexed: 11/23/2022] Open
Abstract
AIM To summarize the phenotypes and identify the underlying genetic cause of the CRYBB1 and CRYBB2 gene responsible for congenital cataract in two Chinese families. METHODS Detailed family histories and clinical data were collected from patients during an ophthalmologic examination. Of 523 inheritable genetic vision system-related genes were captured and sequenced by targeted next-generation sequencing, and the results were confirmed by Sanger sequencing. The possible functional impacts of an amino acid substitution were performed with PolyPhen-2 and SIFT predictions. RESULTS The patients in the two families were affected with congenital cataract. Sixty-five (FAMILY-1) and sixty-two (FAMILY-2) single-nucleotide polymorphisms and indels were selected by recommended filtering criteria. Segregation was then analyzed by applying Sanger sequencing with the family members. A heterozygous CRYBB1 mutation in exon 4 (c.347T>C, p.L116P) was identified in sixteen patients in FAMILY-1. A heterozygous CRYBB2 mutation in exon 5 (c.355G>A, p.G119R) was identified in three patients in FAMILY-2. Each mutation co-segregated with the affected individuals and did not exist in unaffected family members and 200 unrelated normal controls. The mutation was predicted to be highly conservative and to be deleterious by both PolyPhen-2 and SIFT. CONCLUSION The CRYBB1 mutation (c.347T>C) and CRYBB2 mutation (c.355G>A) are novel in patients with congenital cataract. We summarize the variable phenotypes among the patients, which expanded the phenotypic spectrum of congenital cataract in a different ethnic background.
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Affiliation(s)
- Peng Chen
- Qingdao University, Qingdao 266071, Shandong Province, China
| | - Hao Chen
- Qingdao University, Qingdao 266071, Shandong Province, China
| | - Xiao-Jing Pan
- Shandong Eye Institute, Qingdao 266071, Shandong Province, China
| | - Su-Zhen Tang
- Qingdao University, Qingdao 266071, Shandong Province, China
| | - Yu-Jun Xia
- Qingdao University, Qingdao 266071, Shandong Province, China
| | - Hui Zhang
- Jinan Second People's Hospital, Jinan 250022, Shandong Province, China
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26
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Vidya NG, Vasavada AR, Rajkumar S. Evaluating the association of bone morphogenetic protein 4-V152A and SIX homeobox 6-H141N polymorphisms with congenital cataract and microphthalmia in Western Indian population. J Postgrad Med 2018; 64:86-91. [PMID: 29692399 PMCID: PMC5954819 DOI: 10.4103/jpgm.jpgm_219_17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Background: Congenital cataract and microphthalmia are highly heterogeneous congenital eye disorders that affect normal vision. Although mutation in several genes has been shown to cause congenital cataract and microphthalmia, genetic studies associating single-nucleotide polymorphisms with these conditions is scarce. Hence, the present study aims to investigate the association of bone morphogenetic protein 4 (BMP4)-V152A (rs17563), and SIX homeobox 6 (SIX6)-H141N (rs33912345) polymorphisms with congenital cataract and microphthalmia in Western Indian cohorts. Materials and Methods: BMP4-V152A and SIX6-H141N were genotyped in 561 participants comprising of 242 congenital cataracts, 52 microphthalmia, and 267 controls using polymerase chain reaction (PCR) and allele specific oligonucleotide (ASO)-PCR method, respectively. Results: The frequency of BMP4- 152A was found to be significantly different between the cases and controls (Odds ratio (OR) 95% confidence interval [CI] = 1.4 [1.03–1.76], P = 0.0275). The frequency of BMP4- 152AA genotype was found to be significantly higher in congenital cataract cases as compared to controls (OR [95% CI] = 2.1 [1.14–3.67], P = 0.0154. The V-N haplotype of BMP4-V152A and SIX6-H141N was found to have a protective effect toward congenital cataract (OR [95% CI] = 0.72 [0.56–0.94], P = 0.0163) and microphthalmia (OR [95% CI] = 0.63 [0.40–1.01, P = 0.0541). Conclusions: The BMP4- 152AA genotype might play role in the causation of congenital cataract, whereas BMP4-SIX6 V-N haplotype might play a protective role toward the development of congenital cataract and microphthalmia.
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Affiliation(s)
- N G Vidya
- Department of Molecular Genetics and Biochemistry, Iladevi Cataract and IOL Research Centre, Ahmedabad, Gujarat; Ph.D Scholar, Manipal University, Manipal, Karnataka, India
| | - A R Vasavada
- Department of Cataract and Refractive Surgery, Raghudeep Eye Hospital, Ahmedabad, Gujarat, India
| | - S Rajkumar
- Department of Molecular Genetics and Biochemistry, Iladevi Cataract and IOL Research Centre, Ahmedabad, Gujarat, India
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27
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Ceroni F, Aguilera-Garcia D, Chassaing N, Bax DA, Blanco-Kelly F, Ramos P, Tarilonte M, Villaverde C, da Silva LRJ, Ballesta-Martínez MJ, Sanchez-Soler MJ, Holt RJ, Cooper-Charles L, Bruty J, Wallis Y, McMullan D, Hoffman J, Bunyan D, Stewart A, Stewart H, Lachlan K, Fryer A, McKay V, Roume J, Dureau P, Saggar A, Griffiths M, Calvas P, Ayuso C, Corton M, Ragge NK. New GJA8 variants and phenotypes highlight its critical role in a broad spectrum of eye anomalies. Hum Genet 2018; 138:1027-1042. [PMID: 29464339 DOI: 10.1007/s00439-018-1875-2] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2017] [Accepted: 02/09/2018] [Indexed: 12/23/2022]
Abstract
GJA8 encodes connexin 50 (Cx50), a transmembrane protein involved in the formation of lens gap junctions. GJA8 mutations have been linked to early onset cataracts in humans and animal models. In mice, missense mutations and homozygous Gja8 deletions lead to smaller lenses and microphthalmia in addition to cataract, suggesting that Gja8 may play a role in both lens development and ocular growth. Following screening of GJA8 in a cohort of 426 individuals with severe congenital eye anomalies, primarily anophthalmia, microphthalmia and coloboma, we identified four known [p.(Thr39Arg), p.(Trp45Leu), p.(Asp51Asn), and p.(Gly94Arg)] and two novel [p.(Phe70Leu) and p.(Val97Gly)] likely pathogenic variants in seven families. Five of these co-segregated with cataracts and microphthalmia, whereas the variant p.(Gly94Arg) was identified in an individual with congenital aphakia, sclerocornea, microphthalmia and coloboma. Four missense variants of unknown or unlikely clinical significance were also identified. Furthermore, the screening of GJA8 structural variants in a subgroup of 188 individuals identified heterozygous 1q21 microdeletions in five families with coloboma and other ocular and/or extraocular findings. However, the exact genotype-phenotype correlation of these structural variants remains to be established. Our data expand the spectrum of GJA8 variants and associated phenotypes, confirming the importance of this gene in early eye development.
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Affiliation(s)
- Fabiola Ceroni
- Faculty of Health and Life Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK
| | - Domingo Aguilera-Garcia
- Genetics Service, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | - Nicolas Chassaing
- Service de Génétique Médicale, Hôpital Purpan, CHU Toulouse, Toulouse, France
- UMR 1056 Inserm, Université de Toulouse, Toulouse, France
| | - Dorine Arjanne Bax
- Faculty of Health and Life Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK
| | - Fiona Blanco-Kelly
- Genetics Service, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
- Oxford Centre for Genomic Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
- Institute of Ophthalmology, University College London, London, UK
| | - Patricia Ramos
- Genetics Service, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | - Maria Tarilonte
- Genetics Service, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | - Cristina Villaverde
- Genetics Service, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | - Luciana Rodrigues Jacy da Silva
- Genetics Service, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | | | | | - Richard James Holt
- Faculty of Health and Life Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK
| | - Lisa Cooper-Charles
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Jonathan Bruty
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Yvonne Wallis
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Dominic McMullan
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Jonathan Hoffman
- West Midlands Regional Clinical Genetics Service and Birmingham Health Partners, Birmingham Women's and Children's NHS Foundation Trust, Mindelsohn Way, Birmingham, B15 2TG, UK
| | - David Bunyan
- Wessex Regional Genetics Laboratory, Salisbury NHS Foundation Trust, Salisbury, UK
| | - Alison Stewart
- Sheffield Clinical Genetics Department, Northern General Hospital, Sheffield, UK
| | - Helen Stewart
- Oxford Centre for Genomic Medicine, Oxford University Hospitals NHS Foundation Trust, Oxford, UK
| | - Katherine Lachlan
- Wessex Clinical Genetics Service, Princess Anne Hospital, University Hospital Southampton NHS Foundation Trust, Southampton, UK
- Human Genetics and Genomic Medicine, Southampton General Hospital, University of Southampton, Southampton, UK
| | - Alan Fryer
- Cheshire and Merseyside Genetics Service, Liverpool Women's NHS Foundation Trust, Liverpool, UK
| | - Victoria McKay
- Cheshire and Merseyside Genetics Service, Liverpool Women's NHS Foundation Trust, Liverpool, UK
| | - Joëlle Roume
- Department of Clinical Genetics, Centre de Référence "AnDDI Rares", Poissy Hospital GHU PIFO, Poissy, France
| | - Pascal Dureau
- Fondation Ophtalmologique Adolphe-de-Rothschild, Paris, France
| | - Anand Saggar
- Clinical Genetics Unit, St Georges University of London, London, UK
| | - Michael Griffiths
- West Midlands Regional Genetics Laboratory, Birmingham Women's and Children's NHS Foundation Trust, Birmingham, UK
| | - Patrick Calvas
- Service de Génétique Médicale, Hôpital Purpan, CHU Toulouse, Toulouse, France
- UMR 1056 Inserm, Université de Toulouse, Toulouse, France
| | - Carmen Ayuso
- Genetics Service, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | - Marta Corton
- Genetics Service, Instituto de Investigación Sanitaria-Fundación Jiménez Díaz University Hospital, Universidad Autónoma de Madrid (IIS-FJD, UAM), Madrid, Spain
- Centre for Biomedical Network Research on Rare Diseases (CIBERER), ISCIII, Madrid, Spain
| | - Nicola K Ragge
- Faculty of Health and Life Sciences, Oxford Brookes University, Gipsy Lane, Oxford, OX3 0BP, UK.
- West Midlands Regional Clinical Genetics Service and Birmingham Health Partners, Birmingham Women's and Children's NHS Foundation Trust, Mindelsohn Way, Birmingham, B15 2TG, UK.
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Delineation of Novel Autosomal Recessive Mutation in GJA3 and Autosomal Dominant Mutations in GJA8 in Pakistani Congenital Cataract Families. Genes (Basel) 2018; 9:genes9020112. [PMID: 29461512 PMCID: PMC5852608 DOI: 10.3390/genes9020112] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2018] [Revised: 02/09/2018] [Accepted: 02/09/2018] [Indexed: 12/14/2022] Open
Abstract
Congenital cataract is a clinically and genetically heterogeneous disease. The present study was undertaken to find the genetic cause of congenital cataract families. DNA samples of a large consanguineous Pakistani family were genotyped with a high resolution single nucleotide polymorphism Illumina microarray. Homozygosity mapping identified a homozygous region of 4.4 Mb encompassing the gene GJA3. Sanger sequence analysis of the GJA3 gene revealed a novel homozygous variant c.950dup p.(His318ProfsX8) segregating in an autosomal recessive (AR) manner. The previously known mode of inheritance for GJA3 gene mutations in cataract was autosomal dominant (AD) only. The screening of additional probands (n = 41) of cataract families revealed a previously known mutation c.56C>T p.(Thr19Met) in GJA3 gene. In addition, sequencing of the exon-intron boundaries of the GJA8 gene in 41 cataract probands revealed two additional mutations: a novel c.53C>T p.(Ser18Phe) and a known c.175C>G p.(Pro59Ala) mutation, both co-segregating with the disease phenotype in an AD manner. All these mutations are predicted to be pathogenic by in silico analysis and were absent in the control databases. In conclusion, results of the current study enhance our understanding of the genetic basis of cataract, and identified the involvement of the GJA3 in the disease etiology in both AR and AD manners.
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Singh M, Tyagi SC. Genes and genetics in eye diseases: a genomic medicine approach for investigating hereditary and inflammatory ocular disorders. Int J Ophthalmol 2018; 11:117-134. [PMID: 29376001 DOI: 10.18240/ijo.2018.01.20] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 10/31/2017] [Indexed: 12/27/2022] Open
Abstract
Past 25y have witnessed an exponential increase in knowledge and understanding of ocular diseases and their respective genetic underpinnings. As a result, scientists have mapped many genes and their variants that can influence vision and health of our eyes. Based on these findings, it is becoming clear that an early diagnosis employing genetic testing can help evaluate patients' conditions for instituting treatment plan(s) and follow-up care to avoid vision complications later. For example, knowing family history becomes crucial for inherited eye diseases as it can benefit members in family who may have similar eye diseases or predispositions. Therefore, gathering information from an elaborate examination along with complete assessment of past medical illness by ophthalmologists followed by consultation with geneticists can help create a roadmap for making diagnosis and treatment precise and beneficial. In this review, we present an update on ocular genomic medicine that we believe has tremendous potential towards unraveling genetic implications in ocular diseases and patients' susceptibilities. We also discuss translational aspects of genetic ophthalmology and genome engineering that may help advance molecular diagnostics and therapeutics.
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Affiliation(s)
- Mahavir Singh
- Eye and Vision Science Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
| | - Suresh C Tyagi
- Eye and Vision Science Laboratory, Department of Physiology, University of Louisville School of Medicine, Louisville, Kentucky 40202, USA
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Gupta S, Chatterjee S, Mukherjee A, Mutsuddi M. Whole exome sequencing: Uncovering causal genetic variants for ocular diseases. Exp Eye Res 2017; 164:139-150. [PMID: 28844620 DOI: 10.1016/j.exer.2017.08.013] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 08/22/2017] [Accepted: 08/22/2017] [Indexed: 01/23/2023]
Abstract
Identification of causal genetic defects for human diseases took a significant leap when the first generation DNA sequencing technologies enabled biologists extract sequence-based genetic information from living beings. However, these sequencing methods had unavoidable constraints of throughput, scalability, rapidity, and resolution. In this direction, next-generation sequencing (NGS) since the time of its advent has revolutionized the process of gene discovery for both monogenic and multifactorial genetic diseases. Among several variations of NGS, whole exome sequencing (WES) has emerged as a smart strategy that enables identification of disease causing variants present within the coding region of the human genome. The current review focuses primarily on the application of WES in identification of causal variants for ocular diseases. WES has successfully revealed pathogenic variants in a variety of ocular diseases such as retinal degenerations, refractive errors, lens diseases, corneal dystrophies, and developmental ocular defects. It has demonstrated immense potential for molecular diagnosis of genetic ocular diseases. WES has been extensively used in Mendelian and complex cases, familial and sporadic cases, simplex and multiplex cases, and syndromic and non-syndromic cases of ocular diseases. Although many such ocular diseases have been investigated using WES, reports indicate that it has been employed overwhelmingly for heterogeneous retinal degenerations. WES, within a short period of time, has proved to be a cost-effective and promising approach for understanding the genetic basis of ocular diseases.
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Affiliation(s)
- Shashank Gupta
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Souradip Chatterjee
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Ashim Mukherjee
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi 221005, India
| | - Mousumi Mutsuddi
- Department of Molecular and Human Genetics, Institute of Science, Banaras Hindu University, Varanasi 221005, India.
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Zhu X, Zhang S, Chang R, Lu Y. New cataract markers: Mechanisms of disease. Clin Chim Acta 2017; 472:41-45. [PMID: 28705775 DOI: 10.1016/j.cca.2017.07.010] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2017] [Revised: 07/08/2017] [Accepted: 07/09/2017] [Indexed: 11/28/2022]
Abstract
Cataract is caused by nutritional, metabolic, environmental, and genetic factors, and is a significant cause of blindness and visual impairment. In recent years, extensive research into the human genome has revealed that numerous genetic mutations are associated with cataract. These mutations affect a variety of genes, including those encoding crystallin, membrane proteins, cytoskeletal proteins, transcription factors, and metabolism-related proteins. Elucidation of these mutations and the genetic and molecular mechanisms has helped clarify the etiology of cataract and may facilitate its early diagnosis and treatment. This review summarizes recent advances in our knowledge and potential clinical of genetic markers of cataract.
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Affiliation(s)
- Xiangjia Zhu
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Shaohua Zhang
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Ruiqi Chang
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China
| | - Yi Lu
- Department of Ophthalmology, Eye and Ear, Nose, and Throat Hospital, Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Eye Institute, Eye and Ear, Nose, and Throat Hospital of Fudan University, 83 Fenyang Road, Shanghai 200031, People's Republic of China; Key Laboratory of Myopia, Ministry of Health, Shanghai 200031, People's Republic of China; Shanghai Key Laboratory of Visual Impairment and Restoration, Shanghai 200031, People's Republic of China.
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Chen S, Beltrán JF, Esteban-Jurado C, Franch-Expósito S, Castellví-Bel S, Lipkin S, Wei X, Yu H. GeMSTONE: orchestrated prioritization of human germline mutations in the cloud. Nucleic Acids Res 2017; 45:W207-W214. [PMID: 28521008 PMCID: PMC5556704 DOI: 10.1093/nar/gkx398] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/18/2017] [Accepted: 04/28/2017] [Indexed: 12/28/2022] Open
Abstract
Integrative analysis of whole-genome/exome-sequencing data has been challenging, especially for the non-programming research community, as it requires simultaneously managing a large number of computational tools. Even computational biologists find it unexpectedly difficult to reproduce results from others or optimize their strategies in an end-to-end workflow. We introduce Germline Mutation Scoring Tool fOr Next-generation sEquencing data (GeMSTONE), a cloud-based variant prioritization tool with high-level customization and a comprehensive collection of bioinformatics tools and data libraries (http://gemstone.yulab.org/). GeMSTONE generates and readily accepts a shareable 'recipe' file for each run to either replicate previous results or analyze new data with identical parameters and provides a centralized workflow for prioritizing germline mutations in human disease within a streamlined workflow rather than a pool of program executions.
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Affiliation(s)
- Siwei Chen
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853, USA.,Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA.,Department of Molecular Biology and Genetics, Cornell University, Ithaca, NY 14853, USA
| | - Juan F Beltrán
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853, USA.,Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
| | - Clara Esteban-Jurado
- Gastroenterology Department, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), University of Barcelona, 08036 Barcelona, Catalonia, Spain
| | - Sebastià Franch-Expósito
- Gastroenterology Department, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), University of Barcelona, 08036 Barcelona, Catalonia, Spain
| | - Sergi Castellví-Bel
- Gastroenterology Department, Hospital Clínic, Institut d'Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBEREHD), University of Barcelona, 08036 Barcelona, Catalonia, Spain
| | - Steven Lipkin
- Department of Medicine, Weill Cornell College of Medicine, NY 10021, USA
| | - Xiaomu Wei
- Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA.,Department of Medicine, Weill Cornell College of Medicine, NY 10021, USA
| | - Haiyuan Yu
- Department of Biological Statistics and Computational Biology, Cornell University, Ithaca, NY 14853, USA.,Weill Institute for Cell and Molecular Biology, Cornell University, Ithaca, NY 14853, USA
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Shen C, Wang J, Wu X, Wang F, Liu Y, Guo X, Zhang L, Cao Y, Cao X, Ma H. Next-generation sequencing for D47N mutation in Cx50 analysis associated with autosomal dominant congenital cataract in a six-generation Chinese family. BMC Ophthalmol 2017; 17:73. [PMID: 28526010 PMCID: PMC5437554 DOI: 10.1186/s12886-017-0476-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 05/15/2017] [Indexed: 11/26/2022] Open
Abstract
Background Congenital cataract is the most frequent cause of blindness during infancy or early childhood. To date, more than 40 loci associated with congenital cataract have been identified, including at least 26 genes on different chromosomes associated with inherited cataract. This present study aimed to identify the genetic mutation in a six-generation Chinese family affected with congenital cataract. Methods A detailed six-generation Chinese cataract family history and clinical data of the family members were recorded. A total of 27 family members, including 14 affected and 13 unaffected individuals were recruited. Whole exome sequencing was performed to determine the disease-causing mutation. Sanger sequencing was used to confirm the results. Results A known missense mutation, c. 139G > A (p. D47N), in Cx50 was identified. This mutation co-segregated with all affected individuals and was not observed in the unaffected family members or in 100 unrelated controls. The homology modeling showed that the structure of the mutant protein was different with that wild-type Cx50. Conclusions The missense mutation c.139G > A in GJA8 gene is associated with autosomal dominant congenital cataract in a six-generation Chinese family. The result of this present study provides further evidence that the p. D47N mutation in CX50 is a hot-spot mutation.
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Affiliation(s)
- Chao Shen
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Jingbing Wang
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Xiaotang Wu
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Fuchao Wang
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Yang Liu
- Department of Ophthalmology, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Xiaoying Guo
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Lina Zhang
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Yanfei Cao
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Xiuhua Cao
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China
| | - Hongxing Ma
- Department of Clinical Diagnosis, General Hospital of Daqing Oil Field, Daqing, Heilongjiang Province, People's Republic of China.
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Messina-Baas O, Cuevas-Covarrubias SA. Inherited Congenital Cataract: A Guide to Suspect the Genetic Etiology in the Cataract Genesis. Mol Syndromol 2017; 8:58-78. [PMID: 28611546 DOI: 10.1159/000455752] [Citation(s) in RCA: 54] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 12/05/2016] [Indexed: 01/23/2023] Open
Abstract
Cataracts are the principal cause of treatable blindness worldwide. Inherited congenital cataract (CC) shows all types of inheritance patterns in a syndromic and nonsyndromic form. There are more than 100 genes associated with cataract with a predominance of autosomal dominant inheritance. A cataract is defined as an opacity of the lens producing a variation of the refractive index of the lens. This variation derives from modifications in the lens structure resulting in light scattering, frequently a consequence of a significant concentration of high-molecular-weight protein aggregates. The aim of this review is to introduce a guide to identify the gene involved in inherited CC. Due to the manifold clinical and genetic heterogeneity, we discarded the cataract phenotype as a cardinal sign; a 4-group classification with the genes implicated in inherited CC is proposed. We consider that this classification will assist in identifying the probable gene involved in inherited CC.
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Dang FT, Yang FY, Yang YQ, Ge XL, Chen D, Zhang L, Yu XP, Gu F, Zhu YH. A novel mutation of p.F32I in GJA8 in human dominant congenital cataracts. Int J Ophthalmol 2016; 9:1561-1567. [PMID: 27990357 DOI: 10.18240/ijo.2016.11.05] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2015] [Accepted: 06/16/2016] [Indexed: 11/23/2022] Open
Abstract
AIM To identify a causative mutation in a three-generation family with autosomal dominant congenital total cataract and dissect the molecular consequence of the identified mutation. METHODS Clinical and ophthalmological examinations were performed on the affected and unaffected family members. Mutation were screened in recruited family members by polymerase chain reaction (PCR) of the two reported genes (CRYAA and GJA8) which were linked to human total cataracts and direct sequencing of the PCR product. The molecular consequences of the identified mutation was dissected. The plasmids carrying wild-type and mutant mouse ORF of Gja8, coding for connexin 50 (Cx50), were generated and ectopic expressed in 293 cells. Recombinant protein expression and cellular localization of recombinated Cx50 were assessed by confocal microscopy. RESULTS Clinical and ophthalmological examinations were performed on the affected and unaffected family members. Mutation were screened in recruited family members by PCR of the two reported genes (CRYAA and GJA8) which were linked to human total cataracts and direct sequencing of the PCR product. The molecular consequences of the identified mutation was dissected. The plasmids carrying wild-type and mutant mouse ORF of Gja8, coding for Cx50, were generated and ectopic expressed in 293 cells. Recombinant protein expression and cellular localization of recombinated Cx50 were assessed by confocal microscopy. CONCLUSION This study has identified a novel cataract mutation in GJA8, which adds a novel mutation to the existing spectrum of Cx50 mutations with cataract. The molecular consequences of p.F32I mutation in GJA8 exclude instability and the mislocalization of mutant Cx50 protein.
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Affiliation(s)
- Feng-Tao Dang
- Department of Ophthalmology, the First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian Province, China
| | - Fa-Yu Yang
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Ye-Qin Yang
- School of Nursing, Wenzhou Medical University, Wenzhou 325000, Zhejiang Province, China
| | - Xiang-Lian Ge
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Ding Chen
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Liu Zhang
- Department of Ophthalmology, the First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian Province, China
| | - Xin-Ping Yu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Feng Gu
- School of Ophthalmology and Optometry, Eye Hospital, Wenzhou Medical University, State Key Laboratory Cultivation Base and Key Laboratory of Vision Science, Ministry of Health and Zhejiang Provincial Key Laboratory of Ophthalmology and Optometry, Wenzhou 325027, Zhejiang Province, China
| | - Yi-Hua Zhu
- Department of Ophthalmology, the First Affiliated Hospital of Fujian Medical University, Fuzhou 350005, Fujian Province, China
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Ren M, Yang XG, Dang XJ, Xiao JA. Exome sequencing identifies a novel mutation in GJA8 associated with inherited cataract in a Chinese family. Graefes Arch Clin Exp Ophthalmol 2016; 255:141-151. [DOI: 10.1007/s00417-016-3513-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2016] [Revised: 08/30/2016] [Accepted: 10/03/2016] [Indexed: 12/14/2022] Open
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37
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Identification and functional analysis of two novel connexin 50 mutations associated with autosome dominant congenital cataracts. Sci Rep 2016; 6:26551. [PMID: 27216975 PMCID: PMC4877569 DOI: 10.1038/srep26551] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2016] [Accepted: 05/03/2016] [Indexed: 01/14/2023] Open
Abstract
Autosomal dominant congenital cataracts (ADCC) are clinically and genetically heterogeneous diseases. The present study recruited two Chinese families with bilateral nuclear cataract or zonular pulverulent phenotype. Direct sequencing of candidate genes identified two novel missense mutations of Cx50, Cx50P59A (c.175C > G) and Cx50R76H (c.227G > A), both co-segregated well with all affected individuals. Bioinformatics analysis predicted deleterious for both mutations. Functional and cellular behaviors of wild type and mutant Cx50 examined by stably transfecting recombinant systems revealed similar protein expression levels. Protein distribution pattern by fluorescence microscopy showed that Cx50R76H localized at appositional membranes forming gap junctions with enormous cytoplasmic protein accumulation, whereas the Cx50P59A mutation was found inefficient at forming detectable plaques. Cell growth test by MTT assay showed that induction of Cx50P59A decreased cell viability. Our study constitutes the first report that the Cx50P59A and Cx50R76H mutations are associated with ADCC and expands the mutation spectrum of Cx50 in association with congenital cataracts. The genetic, cellular, and functional data suggest that the altered intercellular communication governed by mutated Cx50 proteins may act as the molecular mechanism underlying ADCC, which further confirms the role of Cx50 in the maintenance of human lens transparency.
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Javadiyan S, Craig JE, Souzeau E, Sharma S, Lower KM, Pater J, Casey T, Hodson T, Burdon KP. Recurrent mutation in the crystallin alpha A gene associated with inherited paediatric cataract. BMC Res Notes 2016; 9:83. [PMID: 26867756 PMCID: PMC4750205 DOI: 10.1186/s13104-016-1890-0] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2015] [Accepted: 01/27/2016] [Indexed: 12/18/2022] Open
Abstract
Background Cataract is a major cause of childhood blindness worldwide. The purpose of this study was to determine the genetic cause of paediatric cataract in a South Australian family with a bilateral lamellar paediatric cataract displaying variable phenotypes. Case presentation Fifty-one genes implicated in congenital cataract in human or mouse were sequenced in an affected individual from an Australian (Caucasian) family using a custom Ampliseq library on the Ion Torrent Personal Genome Machine. Reads were mapped against the human genome (hg19) and variants called with the Torrent Suite software. Variants were annotated to dbSNP 137 using Ion Reporter (IR 1.6.2) and were prioritised for validation if they were novel or rare and were predicted to be protein changing. We identified a previously reported oligomerization disrupting mutation, c.62G > A (p.R21Q), in the Crystallin alpha A (CRYAA) gene segregating in this three generation family. No other novel or rare coding mutations were detected in the known cataract genes sequenced. Microsatellite markers were used to compare the haplotypes between the family reported here and a previously published family with the same segregating mutation. Haplotype analysis indicated a potential common ancestry between the two South Australian families with this mutation. The work strengthens the genotype-phenotype correlations between this functional mutation in the crystallin alpha A (CRYAA) gene and paediatric cataract. Conclusion The p.R21Q mutation is the most likely cause of paediatric cataract in this family. The recurrence of this mutation in paediatric cataract families is likely due to a familial relationship. Electronic supplementary material The online version of this article (doi:10.1186/s13104-016-1890-0) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Shari Javadiyan
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia.
| | - Jamie E Craig
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia.
| | - Emmanuelle Souzeau
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia.
| | - Shiwani Sharma
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia.
| | - Karen M Lower
- Department of Haematology and Genetic Pathology, School of Medicine, Flinders University, Adelaide, Australia.
| | - John Pater
- Ophthalmology Department, Women's and Children's Hospital, Adelaide, Australia.
| | - Theresa Casey
- Ophthalmology Department, Women's and Children's Hospital, Adelaide, Australia.
| | | | - Kathryn P Burdon
- Department of Ophthalmology, School of Medicine, Flinders Medical Centre, Flinders University, Rm 4D 111.1, Flinders Dr, Bedford Park, Adelaide, 5042, Australia. .,Menzies Institute for Medical Research, University of Tasmania, Hobart, Australia.
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A novel Cx50 (GJA8) p.H277Y mutation associated with autosomal dominant congenital cataract identified with targeted next-generation sequencing. Graefes Arch Clin Exp Ophthalmol 2015; 253:915-24. [PMID: 25947639 DOI: 10.1007/s00417-015-3019-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2014] [Revised: 04/06/2015] [Accepted: 04/08/2015] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND To unravel the molecular genetic background responsible for autosomal dominant congenital pulverulent nuclear cataracts in a four-generation Chinese family. METHODS Family history data were collected, ophthalmological examinations were performed, and genomic DNA was extracted from peripheral blood of the family members. The candidate genes were captured and sequenced by targeted next-generation sequencing, and the results were confirmed by Sanger sequencing. The structure modelling of the protein was displayed based on Swiss-Model Server, and its possible changes in the secondary structure were predicted using Antheprot 2000 software. The chemical dissimilarity and possible functional impact of an amino acid substitution were performed with Grantham score, PolyPhen-2, and SIFT predictions. Protein distributions were assessed by confocal microscopy. RESULTS A novel heterozygous c.829C > T transition that led to the substitution of a highly conserved histidine by tyrosine at codon 277 (p.H277Y) in the coding region of connexin50 (Cx50, GJA8) was identified. Bioinformatics analysis showed that the mutation likely altered the secondary structure of the protein by replacing the helix of the COOH-terminal portion with a turn. The mutation was predicted to be moderately conservative by Grantham score and to be deleterious by both PolyPhen-2 and SIFT with consistent results. In addition, when expressed in COS1 cells, the mutation led to protein accumulation and caused changes in Cx 50 protein localization pattern. CONCLUSIONS This is a novel missense mutation [c.829C > T, (p.H277Y)] identified in exon 2 of Cx50. Our findings expand the spectrum of Cx50 mutations that are associated with autosomal dominant congenital pulverulent nuclear cataract.
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