Background: The recent studies have demonstrated that polymorphisms of DNA repair genes can impact the tumor susceptibility. So the susceptible group can be chosen through analysis of different genotype of DNA repair genes and maybe get the early prevention, early diagnosis and early treatment. The aim is to analyze the polymorphisms of DNA repair gene ERCC1 and relationship between genetic variations and susceptibility to lung cancer.
Methods: A case-control group study of 291 patients with lung cancer and 273 cancer-free subjects as a control group was conducted to detect ERCC1 polymorphisms at loci. Genotypes of ERCC1 were analyzed by real time PCR techniques using Taqman probes.
Results: In never smoking people, a significant difference was found in the 3 genotype (C/C,C/T,T/T) between cases and controls (Chi-Square=11.19, P <0.01). In never smoking people, compared with homozygous genotype (C/C), ERCC1 codon 118 homozygous genotype (T/T) might increase the risk of lung cancer, the adjusted OR is 3.16 (95%CI: 1.29-7.73, P<0.01).Compared with homozygous genotype (C/C) and never smoking ,those with smoking dose>25 pack-year and homozygous genotype (C/C) or heterozygous genotype (C/T) might increase the risk of lung cancer, the adjusted OR are 2.62(95%CI:1.54-4.44),2.41(95%CI:1.36-4.26,P<0.01)respectively. Compared with homozygous genotype (C/C), homozygous genotype (T/T) might increase the risk adenocarcinoma (OR=2.29, 95%CI: 1.05-4.78, P =0.03).
Conclusions: The results demonstrate that genetic polymorphism of ERCC1 DNA repair gene might contribute the susceptibility to lung cancer and have synergistic effect with smoking.