Dataset Information

A novel mutation in CRYAB associated with autosomal dominant congenital nuclear cataract in a Chinese family.

ABSTRACT: PURPOSE: To identify the genetic defects associated with autosomal dominant congenital nuclear cataract in a Chinese family. METHODS: Clinical data were collected, and the phenotypes of the affected members in this family were recorded by slit-lamp photography. Genomic DNA was isolated from peripheral blood. Mutations were screened in cataract-associated candidate genes through polymerase chain reaction (PCR) analyses and sequencing. Structural models of the wild-type and mutant alphaB-crystallin were generated and analyzed by SWISS-MODEL. RESULTS: Mutation screening identified only one heterozygous G-->A transition at nucleotide 32 in the first exon of alphaB-crystallin (CRYAB), resulting in an amino acid change from arginine to histidine at codon 11 (R11H). This mutation segregated in all available affected family members but was not observed in any of the unaffected persons of the family. The putative mutation disrupted a restriction site for the enzyme, Fnu4HI, in the affected family members. The disruption, however, was not found in any of the randomly selected ophthalmologically normal individuals or in 40 unrelated senile cataract patients. Computer-assisted prediction suggested that this mutation affected the biochemical properties as well as the structure of alphaB-crystallin. CONCLUSIONS: These results supported the idea that the novel R11H mutation was responsible for the autosomal dominant nuclear congenital cataract in this pedigree.

SUBMITTER: Chen Q

PROVIDER: S-EPMC2709425 | biostudies-literature | 2009

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

A novel mutation in CRYAB associated with autosomal dominant congenital nuclear cataract in a Chinese family.

Chen Qiang Q Ma Junjie J Yan Ming M Mothobi Maneo Emily ME Liu Yuanyuan Y Zheng Fang F

Molecular vision 20090710

<h4>Purpose</h4>To identify the genetic defects associated with autosomal dominant congenital nuclear cataract in a Chinese family.<h4>Methods</h4>Clinical data were collected, and the phenotypes of the affected members in this family were recorded by slit-lamp photography. Genomic DNA was isolated from peripheral blood. Mutations were screened in cataract-associated candidate genes through polymerase chain reaction (PCR) analyses and sequencing. Structural models of the wild-type and mutant alp ...[more]

PMID: 19597569

Similar Datasets

Project description: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.

Dataset Information

A novel mutation in CRYAB associated with autosomal dominant congenital nuclear cataract in a Chinese family.

Publications

A novel mutation in CRYAB associated with autosomal dominant congenital nuclear cataract in a Chinese family.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets