Polymorphisms of DNA repair genes and sun exposure as predisposing factors for age related cataract
- نوع فایل : کتاب
- زبان : انگلیسی
- مؤلف : Asmaa Ismail Ahmed & Mohammed Yasser Sayed Saif & Abeer Ahmed Zayed
- چاپ و سال / کشور: 2011
Description
Age-related cataract is a leading cause of blindness throughout the world. Regular exposure to sunlight increases the risk of cataract development. Ultraviolet light causes oxidative stress which induces DNA damage in the lens epithelium and the development of opacities. The existence of DNA repair in lens epithelial cells has been reported, and polymorphisms of DNA repair genes may affect repair efficiency. This work aims to study the frequency of polymorphisms of two DNA repair genes, xeroderma pigmentosum complementation group D (XPD) codon751 and X-ray cross-complementing group 1 (XRCC1) codon399, in cataract in the sunny weather of Egypt. Forty-two Egyptian patients with maturity onset cataract were compared to 41 control subjects using polymerase chain reaction and restriction fragment length polymorphism. There was a significant increase in frequency of XRCC1-399 Arg/Arg genotype in cataract patients (42.8%) compared to healthy controls (22%) (p=0.042). This increase remained significant after redistribution according to occupational exposure. No significant difference was found for the genotypic and allelic distributions of the polymorphisms in XPD-751 gene (p>0.05) between groups. There was a significant increase in cataract development in subjects with high exposure risk to sunlight more than those with low risk, either due to their occupation (p=0.034) or to residence in sunny areas of upper Egypt (p=0.037). Findings suggest that polymorphism in XRCC1 codon399 may predispose to the development of maturity-onset cataract and support the hypothesis that sun exposure is a leading factor for cataract development.
Comp Clin Pathol DOI 10.1007/s00580-011-1290-8 Received: 15 March 2011 / Accepted: 8 July 2011
