Association between XPG polymorphisms and stomach cancer susceptibility in a Chinese population

Xeroderma pigmentosum group G (XPG) protein plays an important role in the DNA repair process by cutting the damaged DNA at the 3 terminus. Previous studies have indicated some polymorphisms in the XPG gene are associated with stomach cancer susceptibility. We performed this hospital-based case-control study to evaluate the association of four potentially functional XPG polymorphisms (rs2094258 C>T, rs751402 C>T, rs2296147 T>C and rs873601G>A) with stomach cancer susceptibility. The four single nucleotide polymorphisms (SNPs) were genotyped in 692 stomach cancer cases and 771 healthy controls. Logistic regression analysis was conducted, and odds ratios (ORs) and 95% confidence intervals (CIs) were used to assess the association of interest. Of the studied SNPs, XPG rs873601G>A polymorphism was found to significantly associate with stomach cancer susceptibility (AA versus GG/AG: OR = 1.31, 95% CI = 1.03-1.66, P = 0.027). Combined analysis of all SNPs revealed that the individuals with two of risk genotypes had a significantly increased stomach cancer risk (OR = 1.52, 95% CI = 1.13-2.06). In the stratification analysis, the association between the rs873601AA genotype and stomach cancer risk was observed in older group (>59 year), as well as patients with non-cardia stomach cancer. Further combined analysis indicated men, smokers, or non-drinkers more than one risk genotypes had a significantly increased stomach cancer risk. Our results indicate that XPG rs873601G>A polymorphism may be associated with the risk of stomach cancer. Further prospective studies with different ethnicities and large sample sizes are needed to validate our findings.