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Liu Y, Ye Z, Yu H, Zhang Y, Li Z. A novel base substitution mutation of the CRYBA2 gene is associated with autosomal dominant congenital cataract. Gene 2024; 927:148726. [PMID: 38909969 DOI: 10.1016/j.gene.2024.148726] [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: 04/07/2024] [Revised: 06/05/2024] [Accepted: 06/20/2024] [Indexed: 06/25/2024]
Abstract
Congenital cataract is one of the leading causes of vision loss in children, and a large proportion of cases are related to genetics. In a Chinese family, we reported a new missense mutation in CRYBA2 (c.223T>C: p.Tyr75His), which can cause autosomal dominant congenital bilateral cataract. We collected blood samples from family members (mother and two sons) and extracted DNA. Through whole-exome sequencing, we discovered a novel unreported mutation. According to relevant ACMG guidelines, this mutation was determined to be a variant of unknown clinical significance. This article further expands the site information on the CRYBA2 mutations.
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Affiliation(s)
- Yuming Liu
- Chinese People's Liberation Army (PLA) Medical School, Beijing 100853, China
| | - Zi Ye
- The Third Medical Center of the PLA General Hospital, China
| | - HanYang Yu
- The Seventh Medical Center of the PLA General Hospital, China
| | - Yan Zhang
- The Seventh Medical Center of the PLA General Hospital, China.
| | - Zhaohui Li
- The Third Medical Center of the PLA General Hospital, China.
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2
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González-Buenfil R, Vieyra-Sánchez S, Quinto-Cortés CD, Oppenheimer SJ, Pomat W, Laman M, Cervantes-Hernández MC, Barberena-Jonas C, Auckland K, Allen A, Allen S, Phipps ME, Huerta-Sanchez E, Ioannidis AG, Mentzer AJ, Moreno-Estrada A. Genetic Signatures of Positive Selection in Human Populations Adapted to High Altitude in Papua New Guinea. Genome Biol Evol 2024; 16:evae161. [PMID: 39173139 PMCID: PMC11339866 DOI: 10.1093/gbe/evae161] [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] [Accepted: 07/09/2024] [Indexed: 08/24/2024] Open
Abstract
Papua New Guinea (PNG) hosts distinct environments mainly represented by the ecoregions of the Highlands and Lowlands that display increased altitude and a predominance of pathogens, respectively. Since its initial peopling approximately 50,000 years ago, inhabitants of these ecoregions might have differentially adapted to the environmental pressures exerted by each of them. However, the genetic basis of adaptation in populations from these areas remains understudied. Here, we investigated signals of positive selection in 62 highlanders and 43 lowlanders across 14 locations in the main island of PNG using whole-genome genotype data from the Oceanian Genome Variation Project (OGVP) and searched for signals of positive selection through population differentiation and haplotype-based selection scans. Additionally, we performed archaic ancestry estimation to detect selection signals in highlanders within introgressed regions of the genome. Among highland populations we identified candidate genes representing known biomarkers for mountain sickness (SAA4, SAA1, PRDX1, LDHA) as well as candidate genes of the Notch signaling pathway (PSEN1, NUMB, RBPJ, MAML3), a novel proposed pathway for high altitude adaptation in multiple organisms. We also identified candidate genes involved in oxidative stress, inflammation, and angiogenesis, processes inducible by hypoxia, as well as in components of the eye lens and the immune response. In contrast, candidate genes in the lowlands are mainly related to the immune response (HLA-DQB1, HLA-DQA2, TAAR6, TAAR9, TAAR8, RNASE4, RNASE6, ANG). Moreover, we find two candidate regions to be also enriched with archaic introgressed segments, suggesting that archaic admixture has played a role in the local adaptation of PNG populations.
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Affiliation(s)
- Ram González-Buenfil
- Advanced Genomics Unit (UGA), Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav), Irapuato, Guanajuato, Mexico
| | - Sofía Vieyra-Sánchez
- Advanced Genomics Unit (UGA), Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav), Irapuato, Guanajuato, Mexico
| | - Consuelo D Quinto-Cortés
- Advanced Genomics Unit (UGA), Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav), Irapuato, Guanajuato, Mexico
| | | | - William Pomat
- Vector-Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Moses Laman
- Vector-Borne Diseases Unit, Papua New Guinea Institute of Medical Research, Madang, Papua New Guinea
| | - Mayté C Cervantes-Hernández
- Advanced Genomics Unit (UGA), Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav), Irapuato, Guanajuato, Mexico
| | - Carmina Barberena-Jonas
- Advanced Genomics Unit (UGA), Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav), Irapuato, Guanajuato, Mexico
| | | | - Angela Allen
- Department of Molecular Haematology, MRC Weatherall Institute of Molecular Medicine, Headley Way, Headington, Oxford, OX3 9DS, UK
| | - Stephen Allen
- Department of Clinical Sciences,Liverpool School of Tropical Medicine, Pembroke Place, Liverpool, L3 5QA, UK
| | - Maude E Phipps
- Jeffrey Cheah School of Medicine and Health Sciences, Monash University Malaysia, Subang Jaya 47500, Selangor, Malaysia
| | - Emilia Huerta-Sanchez
- Center for Computational Molecular Biology, Brown University, Providence, RI 02912, USA
- Department of Ecology, Evolution and Organismal Biology, Brown University, Providence, RI 02912, USA
| | - Alexander G Ioannidis
- Department of Biomolecular Engineering, University of California Santa Cruz, Santa Cruz, CA, USA
- Department of Biomedical Data Science, Stanford Medical School, Stanford, CA, USA
| | | | - Andrés Moreno-Estrada
- Advanced Genomics Unit (UGA), Center for Research and Advanced Studies of the National Polytechnic Institute (Cinvestav), Irapuato, Guanajuato, Mexico
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3
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Nicolas WJ, Shiriaeva A, Martynowycz MW, Grey AC, Ruma Y, Donaldson PJ, Gonen T. Structure of the lens MP20 mediated adhesive junction. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.05.13.594022. [PMID: 38798449 PMCID: PMC11118347 DOI: 10.1101/2024.05.13.594022] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2024]
Abstract
Human lens fiber membrane intrinsic protein MP20 is the second most abundant membrane protein of the human eye lens. Despite decades of effort its structure and function remained elusive. Here, we determined the MicroED structure of full-length human MP20 in lipidic-cubic phase to a resolution of 3.5 Å. MP20 forms tetramers each of which contain 4 transmembrane α-helices that are packed against one another forming a helical bundle. Both the N- and C- termini of MP20 are cytoplasmic. We found that each MP20 tetramer formed adhesive interactions with an opposing tetramer in a head-to-head fashion. These interactions were mediated by the extracellular loops of the protein. The dimensions of the MP20 adhesive junctions are consistent with the 11 nm thin lens junctions. Investigation of MP20 localization in human lenses indicated that in young fiber cells MP20 was stored intracellularly in vesicles and upon fiber cell maturation MP20 inserted into the plasma membrane and restricted the extracellular space. Together these results suggest that MP20 forms lens thin junctions in vivo confirming its role as a structural protein in the human eye lens, essential for its optical transparency.
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Affiliation(s)
- William J. Nicolas
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
| | - Anna Shiriaeva
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Michael W. Martynowycz
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
| | - Angus C Grey
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, NZ
| | - Yasmeen Ruma
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
| | - Paul J Donaldson
- Department of Physiology, School of Medical Sciences, University of Auckland, Auckland, NZ
| | - Tamir Gonen
- Department of Biological Chemistry, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
- Howard Hughes Medical Institute, University of California, Los Angeles, CA 90095
- Department of Physiology, David Geffen School of Medicine, University of California, Los Angeles, CA 90095
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Cvekl A, Camerino MJ. Generation of Lens Progenitor Cells and Lentoid Bodies from Pluripotent Stem Cells: Novel Tools for Human Lens Development and Ocular Disease Etiology. Cells 2022; 11:3516. [PMID: 36359912 PMCID: PMC9658148 DOI: 10.3390/cells11213516] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2022] [Revised: 10/31/2022] [Accepted: 11/02/2022] [Indexed: 11/09/2022] Open
Abstract
In vitro differentiation of human pluripotent stem cells (hPSCs) into specialized tissues and organs represents a powerful approach to gain insight into those cellular and molecular mechanisms regulating human development. Although normal embryonic eye development is a complex process, generation of ocular organoids and specific ocular tissues from pluripotent stem cells has provided invaluable insights into the formation of lineage-committed progenitor cell populations, signal transduction pathways, and self-organization principles. This review provides a comprehensive summary of recent advances in generation of adenohypophyseal, olfactory, and lens placodes, lens progenitor cells and three-dimensional (3D) primitive lenses, "lentoid bodies", and "micro-lenses". These cells are produced alone or "community-grown" with other ocular tissues. Lentoid bodies/micro-lenses generated from human patients carrying mutations in crystallin genes demonstrate proof-of-principle that these cells are suitable for mechanistic studies of cataractogenesis. Taken together, current and emerging advanced in vitro differentiation methods pave the road to understand molecular mechanisms of cataract formation caused by the entire spectrum of mutations in DNA-binding regulatory genes, such as PAX6, SOX2, FOXE3, MAF, PITX3, and HSF4, individual crystallins, and other genes such as BFSP1, BFSP2, EPHA2, GJA3, GJA8, LIM2, MIP, and TDRD7 represented in human cataract patients.
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Affiliation(s)
- Aleš Cvekl
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
| | - Michael John Camerino
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY 10461, USA
- Department of Genetics, Albert Einstein College of Medicine, Bronx, NY 10461, USA
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Berry V, Fujinami K, Mochizuki K, Iwata T, Pontikos N, Quinlan RA, Michaelides M. A recurrent variant in LIM2 causes an isolated congenital sutural/lamellar cataract in a Japanese family. Ophthalmic Genet 2022; 43:622-626. [PMID: 35736209 PMCID: PMC9612932 DOI: 10.1080/13816810.2022.2090010] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Background Genetically determined cataract is both clinically and molecularly highly heterogeneous. Here, we have identified a heterozygous variant in the lens integral membrane protein LIM2, the second most abundant protein in the lens, responsible for congenital sutural/lamellar cataract in a three-generation Japanese family. Methods Whole exome sequencing (WES) was undertaken in one affected and one unaffected individual from a family with autosomal dominant congenital cataract to establish the underlying genetic basis. Results A recurrent missense variant LIM2: c.388C>T; p.R130C was identified and found to co-segregate with disease. In addition, one variant COL11A1:c.3788C>T of unknown significance (VUS) was also identified. Conclusions We report a variant in LIM2 causing an isolated autosomal-dominant congenital sutural/lamellar cataract in a Japanese family. This is the first report of a LIM2 variant in the Japanese population. Hence, we expand the mutation spectrum of LIM2 variants in different ethnic groups.
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Affiliation(s)
- Vanita Berry
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Kaoru Fujinami
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK.,Laboratory of Visual Physiology, Division of Vision Research, National Institute of Sensory Organs, National Hospital Organization, Tokyo Medical Centre, Tokyo, Japan
| | - Kiyofumi Mochizuki
- Department of Ophthalmology, Gifu University Graduate School of Medicine, Gifu, Japan
| | - Takeshi Iwata
- Division of Molecular and Cellular Biology, National Institute of Sensory Organs, National Hospital Organization Tokyo Medical Center, Tokyo, Japan
| | - Nikolas Pontikos
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Roy A Quinlan
- Department of Biosciences, University of Durham, Durham, UK
| | - Michel Michaelides
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
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Biallelic Variants in EPHA2 Identified in Three Large Inbred Families with Early-Onset Cataract. Int J Mol Sci 2021; 22:ijms221910655. [PMID: 34638995 PMCID: PMC8508826 DOI: 10.3390/ijms221910655] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2021] [Revised: 09/27/2021] [Accepted: 09/29/2021] [Indexed: 11/17/2022] Open
Abstract
Hereditary congenital cataract (HCC) is clinically and genetically heterogeneous. We investigated HCC that segregates in three inbred families (LUCC03, LUCC16, and LUCC24). Ophthalmological examinations revealed cataracts with variability related to the age of onset segregating in a recessive manner in these families. Exome sequencing of probands identified a novel homozygous c.2710delG;p.(Val904Cysfs*36) EPHA2 variant in LUCC03 and a known homozygous c.2353G>A;p.(Ala785Thr) EPHA2 variant in the other two recessive families. EPHA2 encodes a transmembrane tyrosine kinase receptor, which is primarily involved in membrane-transport, cell-cell adhesion, and repulsion signaling processes. Computational structural modeling predicts that substitution of a threonine for an alanine p.(Ala785Thr) results in the formation of three new hydrogen bonds with the neighboring residues, which causes misfolding of EPHA2 in both scenarios. Insights from our study will facilitate counseling regarding the molecular and phenotypic landscape of EPHA2-related HCC.
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Fernández-Alcalde C, Nieves-Moreno M, Noval S, Peralta JM, Montaño VEF, del Pozo Á, Santos-Simarro F, Vallespín E. Molecular and Genetic Mechanism of Non-Syndromic Congenital Cataracts. Mutation Screening in Spanish Families. Genes (Basel) 2021; 12:580. [PMID: 33923544 PMCID: PMC8072554 DOI: 10.3390/genes12040580] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2021] [Revised: 04/12/2021] [Accepted: 04/14/2021] [Indexed: 11/28/2022] Open
Abstract
Our purpose was to identify mutations responsible for non-syndromic congenital cataracts through the implementation of next-generation sequencing (NGS) in our center. A sample of peripheral blood was obtained from probands and willing family members and genomic DNA was extracted from leukocytes. DNA was analyzed implementing a panel (OFTv2.1) including 39 known congenital cataracts disease genes. 62 probands from 51 families were recruited. Pathogenic or likely pathogenic variants were identified in 32 patients and 25 families; in 16 families (64%) these were de novo mutations. The mutation detection rate was 49%. Almost all reported mutations were autosomal dominant. Mutations in crystallin genes were found in 30% of the probands. Mutations in membrane proteins were detected in seven families (two in GJA3 and five in GJA8). Mutations in LIM2 and MIP were each found in three families. Other mutations detected affected EPHA2, PAX6, HSF4 and PITX3. Variants classified as of unknown significance were found in 5 families (9.8%), affecting CRYBB3, LIM2, EPHA2, ABCB6 and TDRD7. Mutations lead to different cataract phenotypes within the same family.
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Affiliation(s)
- Celia Fernández-Alcalde
- Department of Ophthalmology, Hospital Universitario La Paz, 28046 Madrid, Spain; (M.N.-M.); (S.N.); (J.M.P.)
| | - María Nieves-Moreno
- Department of Ophthalmology, Hospital Universitario La Paz, 28046 Madrid, Spain; (M.N.-M.); (S.N.); (J.M.P.)
| | - Susana Noval
- Department of Ophthalmology, Hospital Universitario La Paz, 28046 Madrid, Spain; (M.N.-M.); (S.N.); (J.M.P.)
| | - Jesús M. Peralta
- Department of Ophthalmology, Hospital Universitario La Paz, 28046 Madrid, Spain; (M.N.-M.); (S.N.); (J.M.P.)
| | - Victoria E. F. Montaño
- Department of Molecular Ophthalmology, Medical and Molecular Genetics Institute (INGEMM) IdiPaz, CIBERER, Hospital Universitario La Paz, 28046 Madrid, Spain; (V.E.F.M.); (E.V.)
| | - Ángela del Pozo
- Department of Clinical Bioinformatics, Medical and Molecular Genetics Institute (INGEMM) IdiPaz, CIBERER, Hospital Universitario La Paz, 28046 Madrid, Spain;
| | - Fernando Santos-Simarro
- Department of Clinical Genetics, Medical and Molecular Genetics Institute (INGEMM) IdiPaz, CIBERER, Hospital Universitario La Paz, 28046 Madrid, Spain;
| | - Elena Vallespín
- Department of Molecular Ophthalmology, Medical and Molecular Genetics Institute (INGEMM) IdiPaz, CIBERER, Hospital Universitario La Paz, 28046 Madrid, Spain; (V.E.F.M.); (E.V.)
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Wang X, Qin Y, Abudoukeremuahong A, Dongye M, Zhang X, Wang D, Li J, Lin Z, Yang Y, Ding L, Lin H. Elongated axial length and myopia-related fundus changes associated with the Arg130Cys mutation in the LIM2 gene in four Chinese families with congenital cataracts. ANNALS OF TRANSLATIONAL MEDICINE 2021; 9:235. [PMID: 33708862 PMCID: PMC7940952 DOI: 10.21037/atm-20-4275] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Background Congenital cataract (CC) is a congenital abnormality characterized by lens opacity present at birth and is associated with highly heterogeneous clinical manifestations. Lens-specific integral membrane protein (LIM2) gene expression is localized to tight junctional domains of different lens fiber membranes. To date, only four mutations in LIM2 have been reported to be associated with congenital or presenile cataracts. Due to the rarity of variants detected in the gene, there is limited progress in understanding the correlation between the genotype and phenotype of patients with mutations in LIM2. Methods A total of four Chinese families with CCs were recruited for this study, including three families inheriting in an autosomal dominant (AD) pattern and one sporadic case. Genomic DNA was extracted from the leukocytes of peripheral blood collected from all available patients. Whole-exome sequencing (WES) was performed on all probands and at least one of their parents. Bioinformatics analysis was performed to evaluate the pathogenicity of the candidate variants. Exon 4 of LIM2 was amplified by polymerase chain reaction and directly sequenced. All patients underwent full ocular examinations. This was an observational study to explore the genotype-phenotype relationships in the four families with a common candidate variant. Results Various ocular phenotypes were detected in these families, mainly including CCs, elongated axial length, and myopia-related fundus changes. The LIM2 gene mutation, p.Arg130Cys, was detected in all patients. This was further confirmed by Sanger sequencing. The proportion of probands with this mutation in our CCs database was 3.1% (4/130), which indicated that this mutation appears to be a frequent cause of cataracts in the Han Chinese population. This variation has been reported by other investigators before and was correlated with isolated cataracts. Conclusions This is the first study that reports various ocular phenotypes associated with the p.Arg130Cys mutation in the LIM2 gene, which indicated the phenotypic heterogeneity of this gene. LIM2 might not only function as an integral membrane protein in lens fiber cells but also be associated with the axial development of the eyeball. Functional studies of the LIM2 gene are important and should receive more attention.
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Affiliation(s)
- Xun Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yanli Qin
- Department of Ophthalmology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
| | | | - Meimei Dongye
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Xulin Zhang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Dongni Wang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Jing Li
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Zhuoling Lin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Yahan Yang
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
| | - Lin Ding
- Department of Ophthalmology, People's Hospital of Xinjiang Uygur Autonomous Region, Urumqi, China
| | - Haotian Lin
- State Key Laboratory of Ophthalmology, Zhongshan Ophthalmic Center, Sun Yat-sen University, Guangzhou, China
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Pei R, Liang PF, Ye W, Li J, Ma JY, Zhou J. A novel mutation of LIM2 causes autosomal dominant membranous cataract in a Chinese family. Int J Ophthalmol 2020; 13:1512-1520. [PMID: 33078099 DOI: 10.18240/ijo.2020.10.02] [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: 05/11/2020] [Accepted: 07/02/2020] [Indexed: 11/23/2022] Open
Abstract
AIM To identify mutations in the genes of a four-generation Chinese family with congenital membranous cataracts and investigate the morphologic changes and possible functional damage underlying the role of the mutant gene. METHODS Whole exome analysis of thirteen members of a four-generation pedigree affected with congenital membranous cataracts was performed; co-segregation analysis of identified variants was validated by Sanger sequencing. All members underwent detailed physical and complete eye examinations. The physical changes caused by the mutation were analyzed in silico through homology modeling. The lens fiber block from a patient was observed under a scanning electron microscope (SEM). Cell membrane proteins and cytoplasmic proteins from the human lenses donated by one patient with cataract in this family and from the dislocated lens resulted from the penetrating ocular trauma of a patient unrelated with this family were extracted, and the expression and localization of MP20 and Cx46 were detected by Western blot (WB) assay in these proteins. RESULTS A novel LIM2 heterozygous mutation (c.388C>T, p.R130C) was identified with congenital membranous cataracts inherited by an autosomal dominant (AD) pattern. Nystagmus and amblyopia were observed in all patients of this family, and exotropia and long axial length were observed in most patients. A/B ultrasound scan and ultrasound biomicroscopy revealed obvious thin crystalline lenses from 1.7 to 2.7 mm in central thickness in all cataract eyes. The bioinformatic analysis showed that the mutation was deleterious to the physiological function of LIM2-encoded MP20. Furthermore, by SEM, ultrastructure of the cataract nucleus showed that lens fiber cells (LFCs) remained morphologic characteristics of immature fiber cells, including flap cell surface with straight edges and lacking normal ball-and-socket joint boundaries, which implied that the differentiation of LFCs might be inhibited. Accumulation of MP20 and Cx46 in the cytoplasm was observed in the cytoplasm of the LFCs in human cataract lens. CONCLUSION We identify a novel heterozygous LIM2 (c.388C>T, p.R130C) mutation inherited by an AD pattern. This LIM2 mutation causes the abnormal sub-localization of MP20 and Cx46 in LFCs resulting in membranous cataracts.
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Affiliation(s)
- Rui Pei
- Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Peng-Fei Liang
- Department of Otolaryngology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Wei Ye
- Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Ji Li
- Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Ji-Yuan Ma
- Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
| | - Jian Zhou
- Department of Ophthalmology, Xijing Hospital, Fourth Military Medical University, Xi'an 710032, Shaanxi Province, China
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10
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Berry V, Georgiou M, Fujinami K, Quinlan R, Moore A, Michaelides M. Inherited cataracts: molecular genetics, clinical features, disease mechanisms and novel therapeutic approaches. Br J Ophthalmol 2020; 104:1331-1337. [PMID: 32217542 DOI: 10.1136/bjophthalmol-2019-315282] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2019] [Revised: 11/20/2019] [Accepted: 01/28/2020] [Indexed: 02/01/2023]
Abstract
Cataract is the most common cause of blindness in the world; during infancy and early childhood, it frequently results in visual impairment. Congenital cataracts are phenotypically and genotypically heterogeneous and can occur in isolation or in association with other systemic disorders. Significant progress has been made in identifying the molecular genetic basis of cataract; 115 genes to date have been found to be associated with syndromic and non-syndromic cataract and 38 disease-causing genes have been identified to date to be associated with isolated cataract. In this review, we briefly discuss lens development and cataractogenesis, detail the variable cataract phenotypes and molecular mechanisms, including genotype-phenotype correlations, and explore future novel therapeutic avenues including cellular therapies and pharmacological treatments.
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Affiliation(s)
- Vanita Berry
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK
| | - Michalis Georgiou
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Kaoru Fujinami
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,National Institute of Sensory Organs, National Hospital Organization, Tokyo Medical Centre, Tokyo, Japan
| | - Roy Quinlan
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK.,Department of Biosciences, School of Biological and Medical Sciences, University of Durham, Durham, UK
| | - Anthony Moore
- Moorfields Eye Hospital NHS Foundation Trust, London, UK.,Ophthalmology Department, University of California School of Medicine, San Francisco, California, USA
| | - Michel Michaelides
- Department of Genetics, UCL Institute of Ophthalmology, University College London, London, UK .,Moorfields Eye Hospital NHS Foundation Trust, London, UK
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11
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Berry V, Pontikos N, Dudakova L, Moore AT, Quinlan R, Liskova P, Michaelides M. A novel missense mutation in LIM2 causing isolated autosomal dominant congenital cataract. Ophthalmic Genet 2020; 41:131-134. [PMID: 32202185 DOI: 10.1080/13816810.2020.1737950] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Background: Congenital cataract is the most common cause of blindness in the world. Congenital cataracts are clinically and genetically heterogeneous and are mostly inherited in an autosomal dominant fashion. We identified the genetic cause of isolated autosomal dominant cataract in a four-generation British family and a Czech family.Methods: Whole exome sequencing (WES) was performed on one affected member in the British family and two affected members in the Czech family.Results: A novel missense variant c.388C > T; p.(R130C) was identified in the Lens integral membrane protein (LIM2) and found to co-segregate with disease in both families.Conclusions: Here we report the first autosomal dominant congenital cataract variant p.(R130C) in LIM2, causing a non-syndromic pulverulent and nuclear phenotype in European families.
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Affiliation(s)
- Vanita Berry
- UCL Institute of Ophthalmology, University College London, London, UK
| | - Nikolas Pontikos
- UCL Institute of Ophthalmology, University College London, London, UK.,Department of Genetics, Moorfields Eye Hospital NHS Foundation Trust, London, UK
| | - Lubica Dudakova
- Research Unit for Rare Diseases, Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic
| | - Anthony T Moore
- UCL Institute of Ophthalmology, University College London, London, UK.,Ophthalmology Department, University of California School of Medicine, San Francisco, California, USA
| | - Roy Quinlan
- School of Biological and Medical Sciences, University of Durham, Durham, UK
| | - Petra Liskova
- Research Unit for Rare Diseases, Department of Paediatrics and Adolescent Medicine, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic.,Department of Ophthalmology, First Faculty of Medicine, Charles University and General University Hospital, Prague, Czech Republic
| | - Michel Michaelides
- UCL Institute of Ophthalmology, University College London, London, UK.,Department of Genetics, Moorfields Eye Hospital NHS Foundation Trust, London, UK
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12
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Shihan MH, Kanwar M, Wang Y, Jackson EE, Faranda AP, Duncan MK. Fibronectin has multifunctional roles in posterior capsular opacification (PCO). Matrix Biol 2020; 90:79-108. [PMID: 32173580 DOI: 10.1016/j.matbio.2020.02.004] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2019] [Revised: 02/10/2020] [Accepted: 02/25/2020] [Indexed: 12/26/2022]
Abstract
Fibrotic posterior capsular opacification (PCO), one of the major complications of cataract surgery, occurs when lens epithelial cells (LCs) left behind post cataract surgery (PCS) undergo epithelial to mesenchymal transition, migrate into the optical axis and produce opaque scar tissue. LCs left behind PCS robustly produce fibronectin, although its roles in fibrotic PCO are not known. In order to determine the function of fibronectin in PCO pathogenesis, we created mice lacking the fibronectin gene (FN conditional knock out -FNcKO) from the lens. While animals from this line have normal lenses, upon lens fiber cell removal which models cataract surgery, FNcKO LCs exhibit a greatly attenuated fibrotic response from 3 days PCS onward as assessed by a reduction in surgery-induced cell proliferation, and fibrotic extracellular matrix (ECM) production and deposition. This is correlated with less upregulation of Transforming Growth Factor β (TGFβ) and integrin signaling in FNcKO LCs PCS concomitant with sustained Bone Morphogenetic Protein (BMP) signaling and elevation of the epithelial cell marker E cadherin. Although the initial fibrotic response of FNcKO LCs was qualitatively normal at 48 h PCS as measured by the upregulation of fibrotic marker protein αSMA, RNA sequencing revealed that the fibrotic response was already quantitatively attenuated at this time, as measured by the upregulation of mRNAs encoding molecules that control, and are controlled by, TGFβ signaling, including many known markers of fibrosis. Most notably, gremlin-1, a known regulator of TGFβ superfamily signaling, was upregulated sharply in WT LCs PCS, while this response was attenuated in FNcKO LCs. As exogenous administration of either active TGFβ1 or gremlin-1 to FNcKO lens capsular bags rescued the attenuated fibrotic response of fibronectin null LCs PCS including the loss of SMAD2/3 phosphorylation, this suggests that fibronectin plays multifunctional roles in fibrotic PCO development.
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Affiliation(s)
- Mahbubul H Shihan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Mallika Kanwar
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Yan Wang
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Erin E Jackson
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Adam P Faranda
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA
| | - Melinda K Duncan
- Department of Biological Sciences, University of Delaware, Newark, DE 19716, USA.
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13
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Zhao Y, Wilmarth PA, Cheng C, Limi S, Fowler VM, Zheng D, David LL, Cvekl A. Proteome-transcriptome analysis and proteome remodeling in mouse lens epithelium and fibers. Exp Eye Res 2019; 179:32-46. [PMID: 30359574 PMCID: PMC6360118 DOI: 10.1016/j.exer.2018.10.011] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2018] [Revised: 08/31/2018] [Accepted: 10/20/2018] [Indexed: 12/21/2022]
Abstract
Epithelial cells and differentiated fiber cells represent distinct compartments in the ocular lens. While previous studies have revealed proteins that are preferentially expressed in epithelial vs. fiber cells, a comprehensive proteomics library comparing the molecular compositions of epithelial vs. fiber cells is essential for understanding lens formation, function, disease and regenerative potential, and for efficient differentiation of pluripotent stem cells for modeling of lens development and pathology in vitro. To compare protein compositions between the lens epithelium and fibers, we employed tandem mass spectrometry (2D-LC/MS) analysis of microdissected mouse P0.5 lenses. Functional classifications of the top 525 identified proteins into gene ontology categories by molecular processes and subcellular localizations, were adapted for the lens. Expression levels of both epithelial and fiber proteomes were compared with whole lens proteome and mRNA levels using E14.5, E16.5, E18.5, and P0.5 RNA-Seq data sets. During this developmental time window, multiple complex biosynthetic and catabolic processes generate the molecular and structural foundation for lens transparency. As expected, crystallins showed a high correlation between their mRNA and protein levels. Comprehensive data analysis confirmed and/or predicted roles for transcription factors (TFs), RNA-binding proteins (e.g. Carhsp1), translational apparatus including ribosomal heterogeneity and initiation factors, microtubules, cytoskeletal [e.g. non-muscle myosin IIA heavy chain (Myh9) and βB2-spectrin (Sptbn2)] and membrane proteins in lens formation and maturation. Our data highlighted many proteins with unknown functions in the lens that were preferentially enriched in epithelium or fibers, setting the stage for future studies to further dissect the roles of these proteins in fiber cell differentiation vs. epithelial cell maintenance. In conclusion, the present proteomic datasets represent the first mouse lens epithelium and fiber cell proteomes, establish comparative analyses of protein and RNA-Seq data, and characterize the major proteome remodeling required to form the mature lens fiber cells.
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Affiliation(s)
- Yilin Zhao
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Phillip A Wilmarth
- Department of Biochemistry & Molecular Biology, Oregon Health Sciences University, 3181 Southwest Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Catherine Cheng
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Saima Limi
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA
| | - Velia M Fowler
- Department of Molecular Medicine, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Deyou Zheng
- Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Neurology, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Neuroscience, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Department of Neurosurgery, Shanghai East Hospital, Tongji University School of Medicine, Shanghai, 200120, China
| | - Larry L David
- Department of Biochemistry & Molecular Biology, Oregon Health Sciences University, 3181 Southwest Sam Jackson Park Road, Portland, OR, 97239, USA
| | - Ales Cvekl
- Departments Ophthalmology and Visual Sciences, Albert Einstein College of Medicine, Bronx, NY, 10461, USA; Genetics, Albert Einstein College of Medicine, Bronx, NY, 10461, USA.
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14
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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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15
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Magwebu ZE, Abdul-Rasool S, Seier JV, Chauke CG. Autosomal recessive congenital cataract in captive-bred vervet monkeys (Chlorocebus aethiops). J Med Primatol 2018; 47:93-100. [DOI: 10.1111/jmp.12332] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/01/2018] [Indexed: 11/29/2022]
Affiliation(s)
- Zandisiwe E. Magwebu
- Primate Unit and Delft Animal Centre (PUDAC); South African Medical Research Council (SAMRC); Tygerberg Cape Town South Africa
- Medical Bioscience Department; University of the Western Cape; Belville South Africa
| | - Sahar Abdul-Rasool
- Medical Bioscience Department; University of the Western Cape; Belville South Africa
| | - Jürgen V. Seier
- Primate Unit and Delft Animal Centre (PUDAC); South African Medical Research Council (SAMRC); Tygerberg Cape Town South Africa
| | - Chesa G. Chauke
- Primate Unit and Delft Animal Centre (PUDAC); South African Medical Research Council (SAMRC); Tygerberg Cape Town South Africa
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16
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Fine mapping of chromosome 9 locus associated with congenital cataract. Int Ophthalmol 2017; 38:1187-1192. [PMID: 28585112 DOI: 10.1007/s10792-017-0581-8] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2016] [Accepted: 05/31/2017] [Indexed: 10/19/2022]
Abstract
PURPOSE The purpose of this study was to study the molecular basis of inherited autosomal recessive cataracts in Pakistan population and to identify the molecular defect segregating with the disease phenotype. METHODS Families having two or more affected individuals were identified through hospital, blood samples were collected and DNA was extracted. We employed the traditional strategy of linkage analysis using M13-labeled primers to map the already known genes for autosomal recessive cataract. Statistically, the data were evaluated through LOD score. RESULTS Ten families affected with autosomal receive congenital cataract were enrolled for this study. Overall, three families were linked to reported loci for autosomal recessive congenital cataract. Out of these, one family Bl05 was linked to a cataract locus at 9q13. Fine mapping of the chromosome 9 locus considerably delimited the previously reported linkage interval from 13.99 to 7.99 cM in this study. CONCLUSION Our results reduced the linkage interval of previously reported cataract locus on chromosome 9, thus considerably reducing the number of candidate genes.
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Cui XJ, Lv FY, Li FH, Zeng K. Correlations of single nucleotide polymorphisms of CRYAA and CRYAB genes with the risk and clinicopathological features of children suffering from congenital cataract. Medicine (Baltimore) 2017; 96:e7158. [PMID: 28640093 PMCID: PMC5484201 DOI: 10.1097/md.0000000000007158] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/31/2022] Open
Abstract
BACKGROUND The study aims to explore the correlations of the single nucleotide polymorphisms (SNPs) of CRYAA and CRYAB with the risk and clinicopathological features of children with congenital cataract. METHODS The study enrolled 168 children diagnosed as congenital cataract (case group) and 172 normal children (control group) from May 2015 to May 2016. Genomic DNA extraction was performed using a QIAamp DNA blood mini kit. Polymerase chain reaction (PCR) products were genotyped using an ABI direct sequencer. Haplotype, allele, and genotype frequencies of CRYAA and CRYAB gene polymorphisms analyses were carried out using the SHEsis software. Logistic regression analysis was performed in order to analyze the risk factors for children suffering from congenital cataract. RESULTS Presence of significant differences between the case and control groups' genotype and allele frequencies of CRYAA rs7278468 and CRYAB rs370803064/rs387907338. TA of CRYAB gene might increase congenital cataract risk in children, while GCG of CRYAA gene and GC of CRYAB gene might decrease congenital cataract risk in children. CRYAA rs7278468, CRYAB rs370803064/rs387907338 polymorphisms were significantly correlated to uncorrected visual acuity, best-corrected visual acuity, nystagmus, visual axis opacification, microcornea, lens opacity, posterior capsular thickening, and degrees of posterior capsule opacification after operation in children with congenital cataract. Logistic regression analysis revealed that the T allele of CRYAA rs7278468, A allele of CRYAB rs370803064, T allele of CRYAB rs387907338, family history, and TA haplotype of CRYAB gene were risk factors for children with congenital cataract. CONCLUSION Our findings demonstrated that CRYAA rs7278468 and CRYAB rs370803064/rs387907338 are correlated with the risk and clinicopathological features of children suffering from congenital cataract.
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Affiliation(s)
- Xian-Jin Cui
- Department of Ophthalmology, Linyi People's Hospital
| | - Feng-Yan Lv
- Department of Infectious Diseases, Affiliated Hospital of Shandong Medical College, Linyi
| | - Feng-Hua Li
- Department of Ophthalmology, Linyi People's Hospital
| | - Kun Zeng
- Shenzhen Key Laboratory of Ophthalmology, Shenzhen Eye Hospital, Shenzhen, P.R. China
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