Polymorphisms of DNA Repair Genes XPD (Lys751Gln) and XRCC1 (Arg399Gln), and The Risk of Age-Related Cataract: A Meta-Analysis

Abstract

Purpose: A meta-analysis of available studies was used to test the association between two DNA repair genes and age-related cataract.Materials and Methods: A systematic search of the Chinese National Knowledge Infrastructure, EMBASE and PubMed databases identified six studies that were analyzed. Meta-analysis was used to evaluate single nucleotide polymorphisms (SNP) of the DNA repair gene xeroderma pigmentosum complementation group D (XPD) (Lys751Gln) and the X-ray repair cross-complementing gene 1 (XRCC1) (Arg399Gln). Only articles published before June 6, 2014, were included. The quality of the studies was determined using Newcastle–Ottawa Scale tools. The summary odds ratio (OR) and corresponding confidence interval (CI) for XPD Lys751Gln and XRCC1 Arg399Gln polymorphisms and risk of age-related cataract were estimated by random and fixed-effects models. Sensitivity analysis was employed to determine the robustness of the conclusions.Results: Six studies, with a total of 1518 patients with cataractous lenses and 1437 subjects with clear lenses, were included in the meta-analysis. XRCC1 Arg399Gln polymorphisms were associated with cataract risk (recessive model: ORfixed = 0.79, 95% CI: 0.67–0.93; dominant model: ORfixed = 0.84, 95% CI: 0.64–1.11; additive model: ORfixed = 0.82, 95% CI: 0.72–0.92). Analysis of Chinese, but not non-Chinese subgroups, confirmed this association. The OR of XPD Lys751Gln polymorphisms for cataract was not significant. The associations remained significant after sensitivity analysis.Conclusions: This meta-analysis indicates that XRCC1 Arg399Gln polymorphisms, but not XPD Lys751Gln polymorphisms, are associated with risk of age-related cataract.