Lack of DLAD mutations in age-related nuclear cataract

DNase II like acid DNase (DNase IIβ, DLAD) is expressed in human and murine cells in the lens. Studies in mice have reported that abnormal degeneration of cellular organelles by DLAD reduced lens transparency and that the DLAD gene may be involved in cataract formation. The aim of the present study was to search for possible genetic alterations in the DLAD gene in human senile cataract. Anterior lens capsule material was collected during surgery from 55 patients with senile cataract, with or without a subcapsular component. Total DNA was extracted, amplified by polymerase chain reaction and sequenced for exon 3 (n = 51) exon 4 (n = 40) and all 6 exons of the DLAD gene (n = 27). No mutation was found. There were genomic polymorphisms in all exons except 3 and 4. Nonsynonymous genomic polymorphisms were detected in exon 1 (rs738573) and exon 2 (rs3754274) and synonymous polymorphisms were detected in exon 5 (rs7511984) and exon 6 (rs3768250). In contrast to findings in mice, based on the limited samples analyzed, this study suggests that human age-related nuclear cataract is not associated with DLAD mutations.