The relationship between five non-synonymous polymorphisms within three XRCC genes and gastric cancer risk in a Han Chinese population

We aimed to assess the association of five non-synonymous polymorphisms within three X-ray repair cross-complementing group (XRCC) genes with gastric cancer risk in Han Chinese. Genotyping was determined in 693 gastric cancer patients and 681 healthy controls. Statistical analyses were completed with SPSS (version 20.0) and Haplo.stats (version 1.6.11). The genotypes of XRCC1 gene rs25487 polymorphism (P = 0.003) differed significantly between patients and controls, even after the Bonferroni correction (P < 0.05/5), and this polymorphism was significantly associated with gastric cancer after adjusting for age, sex, body mass index, smoking, drinking, especially under a dominant model (odds ratio or OR; 95 % confidence interval or CI; P 1.59; 1.20–2.00; 0.001). In multiple-marker analysis, the most common allele combination was C-G-G-G-C (alleles in order of rs1799782, rs25489, rs25487, rs3218536, rs861539), which was overrepresented in controls relative to patients (adjusted simulated P = 0.0001). Contrastingly, the frequency of allele combination C-G-A-G-C was significantly higher in patients than in controls (adjusted simulated P = 0.0009), and this combination was associated with a strikingly increased risk of gastric cancer (OR; 95 % CI; P 2.39; 1.32–4.31; 0.0040) after the Bonferroni correction (P < 0.05/11) and adjusting for confounders. Our findings demonstrated that XRCC1 gene rs25487 polymorphism might play a leading role in pronounced susceptibility to gastric cancer in Han Chinese.