Association between the -77T>C polymorphism in the DNA repair gene XRCC1 and lung cancer risk

Numerous studies have evaluated the association between the X-ray repair cross-complementing group 1 (XRCC1) DNA repair gene polymorphism -77T>C and lung cancer risk. However, this association is controversial. We used PubMed and Embase to identify 5 case-control studies, which included 2488 lung cancer cases and 2576 controls, for inclusion in a comprehensive meta-analysis in order to assess this association. Two independent reviewers extracted data from the studies, and ORs with 95%CIs were calculated. When all studies were pooled, we found a significant association between the -77T>C polymorphism and lung cancer risk (TT vs CC: OR = 0.52, 95%CI = 0.34-0.80, P = 0.49; TT vs CT: OR = 0.71, 95%CI = 0.62-0.81, P = 0.69; dominant model: OR = 1.45, 95%CI = 1.27-1.66, P = 0.64; recessive model: OR = 0.54, 95%CI = 0.36-0.82, P = 0.24). In a subgroup analysis of nationalities, the -77T>C polymorphism was significantly associated with lung cancer risk in Asian patients. In conclusion, the XRCC1 -77T>C polymorphism might be related to increased risk of lung cancer in Asians. Future studies are needed for conclusive evidence about this association.