[Analysis on gene mutations in a Chinese pedigree with autosomal dominant inheritance cataract]

The aim of this study was to reveal the genetic defect of the autosomal dominant inheritance cataract in a Chinese pedigree.

Case-control study. There were 26 individuals investigated with clinical examination in a Chinese four generations pedigree. The genome DNA of the individuals was extracted by the improved NaI method. The exons of six cataract candidate genes in 204 normal controls and 42 senile cataract patients were screened for the mutation by PCR restriction fragment length polymorphism (PCR-RFLP) methods.

The phenotype of the cataract was pulverulent nuclear cataract. A novel C/T transition at nucleotide position 827 was identified in the GJA8 gene that led to a serine to phenylalanine change in codon 276. This mutation was not found in 42 senile cataract patients and in 204 controls. Four single nucleotide polymorphisms (SNPs) were also found in a cataract candidate gene in the family members.

A novel GJA8 gene mutation was found in a Chinese autosomal dominant inheritance cataract pedigree. A substitution, C276T in GJA8 gene, was identified as the most likely causative mutation underlying the phenotype of pulverulent nuclear cataract in all affected family members.