title: Polymorphisms of the DNA repair genes XPD and XRCC1 and the risk of age-related cataract development in Han Chinese.
abstract: OBJECTIVE
  Epidemiological evidence suggests that ultraviolet (UV) irradiation and oxidative stress play an important role in age-related cataract pathogenesis. UV irradiation and oxidative stress can produce a wide range of DNA damage. Polymorphisms of DNA repair enzymes may affect repair efficiency and the role of DNA repair mechanisms has received attention recently in age-related cataract pathogenesis. In this case-control study, The aim was to determine the frequency of polymorphisms in two DNA repair enzyme genes, xeroderma pigmentosum complementation group D (XPD) codon 751 and x-ray cross-complementing group 1 (XRCC1) codon 399, in patients with age-related cataract and in healthy controls.
  
  
  METHODS
  Polymerase chain reaction and restriction fragment length polymorphisms were used to analyze XPD T751G and XRCC1 G399A in 180 patients with age-related cataract and 174 healthy individuals as controls.
  
  
  RESULTS
  There was a significant difference between the case and control groups in the XRCC1399 genotype. The odds ratio of the XRCC1 G/A polymorphism compared with the G/G wild-type genotype was 1.92 (95% CI = 1.17-3.15, p = 0.01). Moreover, individuals who carried at least one A-allele (G/A or A/A) had a 1.68-fold increased risk of developing age-related cataract compared with those who carried the G/G wild type genotype (OR = 1.68; 95% CI: 1.05-2.68, p = 0.030). No statistically significant difference was found in the genotypic and allelic distributions of the polymorphisms in the XPD gene between the groups.
  
  
  CONCLUSIONS
  These results suggest that polymorphisms in XRCC1 codon 399 may be associated with the development of age-related cataract in Han Chinese.
authors: Department of Ophthalmology, Second Affiliated Hospital of Harbin Medical University, Harbin, China.
authors: Yong-Feng
authors: YF
authors: Luo
authors: Bin-Bin
authors: BB
authors: Wang
authors: Zhou
authors: Z
authors: Zhou
authors: Xu-Chen
authors: XC
authors: Ding
authors: Shan-Shan
authors: SS
authors: Hu
authors: Guang-Kai
authors: GK
authors: Zhou
authors: Xu
authors: X
authors: Ma
authors: Yan-Hua
authors: YH
authors: Qi