LIG3 gene polymorphisms and risk of gastric cancer in a Southern Chinese population.

DNA ligase III (LIG3) has been implicated in the etiology of cancer. However, few studies have accessed the association of LIG3 single nucleotide polymorphisms (SNPs) with gastric cancer risk, especially in Chinese population. The current study was undertaken to investigate contribution of LIG3 gene polymorphisms to gastric cancer risk. We first applied TaqMan assay to genotype three LIG3 gene SNPs (rs1052536 C > T, rs3744356 C > T, rs4796030 A > C) in 1142 patients with gastric cancer and 1173 healthy controls. And then, we adopted unconditional multivariate logistic regression analysis to estimate the association between LIG3 SNP genotypes and gastric cancer risk. In all, no positive association was found between the three LIG3 SNPs and gastric cancer risk in single locus analysis or combined risk genotypes analysis. However, compared with participants with rs4796030 AA genotype, participants with the AC/CC had a decreased risk of developing tumors from cardia at an adjusted OR of 0.68 (95% CI = 0.48-0.96, P = 0.026). In addition, we found that participants harboring 2-3 risk genotypes were at a significantly increased risk of developing tumor from cardia (adjusted OR = 1.63, 95% CI = 1.16-2.28, P = 0.005). These results suggest that genetic variations in LIG3 gene may play a weak role in modifying the risk of gastric cancer. Future functional studies should be performed to elucidate the biological role of LIG3 polymorphisms in gastric cancer carcinogenesis.