Genotype of DNA double-strand break repair gene XRCC7 is associated with lung cancer risk in Taiwan males and smokers.

AIM: The present study aimed to evaluate the contribution of X-ray repair cross-complementing group 7 (XRCC7) G6721T (rs7003908) genetic polymorphism and smoking habit on the risk of lung cancer in Taiwanese. MATERIALS AND METHODS: In this hospital-based case-control study, association of single nucleotide polymorphism XRCC7 G6721T with lung cancer risk were examined among 358 patients with lung cancer and 716 age- and gender-matched healthy controls. The genetic-lifestyle interaction was also investigated. RESULTS: The results showed that the percentages of TT, GT and GG genotypes for XRCC7 G6721T were differentially distributed as 60.9%, 34.9% and 4.2% in the group of patients with lung cancer and 48.7%, 43.3% and 8.0% in the non-cancer control group, respectively (p=3.6*10(-7)). We further stratified the populations by gender and smoking behavior to investigate their combinatorial effects with XRCC7 G6721T genotype on lung cancer risk. The results showed that the GG genotype of XRCC7 G6721T had a protective effect on lung cancer susceptibility which was obvious among males and smokers (p=2.2×10(-4) and 3.1×10(-4), respectively). CONCLUSION: The GG and GT genotypes of XRCC7 rs7003908 compared to the TT genotype had a protective effect on lung cancer risk in Taiwan, particularly among males and smokers.