Crystalline gene mutations in Turkish children with congenital cataracts

Abstract

Purpose: To detect crystallin gene mutations in Turkish children with congenital cataracts.

Methods: The present study included 56 children (38 males and 18 females) who were diagnosed with congenital cataract in our ophthalmology clinic. The patients' blood samples were collected and sent to the medical genetics laboratory. The samples were assessed using the sequence analysis method, which covered all exons of CRYAA, CRYAB, CRYBB1, CRYBB2, CRYBB3, CRYGC and CRYGD.

Results: In total, 56 patients with congenital cataracts were included in the present study. Of these, 68% were male and 32% were female. The age range of the patients was 2 months to 5 years. The mean age of onset was 21.08 ± 15.15 months. All the patients had bilateral congenital cataracts. The female-to-male ratio was 1:2.1. Mutation analysis was performed to detect possible mutations in CRYAA, CRYAB, CRYBB1, CRYBB2, CRYBB3, CRYGC and CRYGD. Of the four mutations detected, one was novel (c.383A > T in CRYGD) and three were known (c.592C > T in CRYBB2, c.164A > G in CRYGC and c.592C > T in CRYBB2). Two of these three mutations were detected in the same gene (CRYBB2). Crystallin gene mutations were detected in 7% of patients with congenital cataracts (four out of 56 patients) in the present study.

Conclusions: We think that mutations in crystallin genes are responsible for 7% of congenital cataract cases in our country. The detection of these mutations may help in the molecular diagnosis of congenital cataracts.

Keywords: Congenital cataract; Crystalline gene; Genetic.