Objective: To explore the relationship between the polymorphisms of DNA repair gene XRCC1 and susceptibility to pulmonary cancer.
Methods: A case-control study of 209 lung cancer patients and 256 control subjects was conducted to investigate the role of XRCC1 gene in lung cancer. Genotyping was performed using PCR based restriction fragment length polymorphism (PCR-RFLP) technique.
Results: The frequency (19.1%) of XRCC1-194 Trp/Trp in case group was significantly higher than that (10.9%) in control group (P < 0.05), OR for lung cancer was 2.215 (95% CI: 1.276-3.845). The frequency (6.7%) of XRCC1-280 His/His in case group was significantly higher than that (4.3%) in control group (P < 0.05), OR for lung cancer was 2.46 (95% CI: 1.141-5.304). There was no significant difference for XRCC1-399 Gln/Gln genotype between the two groups. Interaction analysis of gene polymorphisms and environment factors indicated that there was interactions between XRCC1-194 Trp/Trp and XRCC1-280 His/His genotypes and smoking. The risks of lung cancer in smokers with XRCC1-194 Arg/Trp+Trp/Trp and XRCC1-280 His/His+Arg/His were 4.889 (95% CI: 2.828-8.452) and 6.281(95% CI: 3.572-11.046), respectively.
Conclusion: These findings supported the hypothesis that the interaction of polymorphisms of XRCC1-194 Trp/Trp, XRCC1-280 His/His with smoking resulted in the increased risk of lung cancer, and the polymorphisms of XRCC and smoking could play an role in development of lung cancer.