Objective   To evaluate the correlation of the single nucleotide polymorphism of XRCC1 and smoking, independently and in combination with the risk of lung cancer.

  Methods   A case-control study of 149 lung cancer patients and 157 control subjects(matched for age, sex)was conducted to investigate the role of XRCC1 gene in lung cancer.Genotyping was performed using PCR based restriction fragment length polymorhphism techniques.The adjusted odds ratio(OR)and 95% confidence interval(CI)was calculated using multivariate logistic regressing.

  Results   The frequency of TTallele in case group(12.8%)was significantly higher than that in control group(6.4%), with the OR for lung cancer being 2.0(adjusted OR=116, 95%CI 0.57-4.47).The frequency of AA allele in case group(10.7%)was significantly higher than that in control group(8.3%), with the adjusted OR for lung cancer being 2.1(95%CI 0.73-6.15).Further more, the risk of lung cancer for XRCC1 genety pes appeared to be pronounced compared with nonsmokers.But no inter action was found between two either genetype.

  Conclusion   These findings support the hypot hesis which the polymorphsm of XRCC1 and its correlation with smoking do contribute to the risk of developing lung cancer.