Further evidence for P59L mutation in GJA3 associated with autosomal dominant congenital cataract

CONTEXT: Congenital cataracts are one of the common eye disorders leading to visual impairment or blindness in children worldwide. We found a Chinese family with autosomal dominant pulverulent cataract. AIMS: To identify the pathogenic gene mutation in a Chinese family with autosomal dominant inherited pulverulent cataract. SUBJECTS AND METHODS: After obtained informed consent, detailed ophthalmic examinations were carried out; genomic DNAs were obtained from seven family members in a three-generation Chinese family with three affected. All exons of candidate genes were amplified by polymerase chain reaction and were sequenced performed by bidirectional sequencing. RESULTS: By sequencing the encoding regions of the candidate genes, a missense mutation (c. 176C>T) was detected in gap junction protein alpha 3 genes (GJA3), which resulted in the substitution of highly conserved proline by leucine at codon 59 (p.P59L). The mutation co-segregated with all patients and was absent in 100 normal Chinese controls. CONCLUSIONS: The study identified a missense mutation (c. 176C>T) in GJA3 gene associated with autosomal dominant congenital pulverulent cataract in a Chinese family. It gave further evidence of phenotype heterogeneity for P59L mutation in GJA3 associated with congenital cataract.