A recurrent mutation in CRYBA1 is associated with an autosomal dominant congenital nuclear cataract disease in a Chinese family

PURPOSE: Congenital cataracts are a clinically and genetically heterogeneous lens disorder. The purpose of this study was to identify the genetic mutation and the molecular phenotype responsible for the presence of an autosomal dominant congenital nuclear cataract disease in a Chinese family. METHODS: Patients were given a physical examination and their blood samples were collected for DNA extraction. Genotyping was performed by microsatellite markers, and a logarithm of odds (LOD) score was calculated using the LINKAGE programs. Mutation detection was performed by direct sequencing. RESULTS: Linkage to the crystallin beta A1 (CRYBA1) locus was identified. DNA sequencing of the gene revealed a c.279–281delGAG mutation in exon 4, which resulted in a glycine residue deletion at position 91 (ΔG91). This mutation was identified in all of the affected individuals but was not found in the 100 control chromosomes. CONCLUSIONS: Our results identify that the c.279–281delGAG mutation in CRYBA1 is responsible for the autosomal dominant congenital nuclear cataract disease in this Chinese family.