Association analysis of selenoprotein S polymorphisms in Chinese Han with susceptibility to gastric cancer.

OBJECTIVE selenoprotein S (SelS) gene polymorphism is closely related to a variety of malignant tumours. Here, we evaluate the association between SelS polymorphism and genetic susceptibility to gastric cancer. METHODS A case-control study was conducted to investigate the role of two SelS single nucleotide polymorphisms (SNPs) on the susceptibility to gastric cancer. The genotypes and genotype frequencies of the SelS were determined in 260 gastric cancer patients and 278 age-matched healthy controls. Polymerase chain reaction restriction fragment length of polymorphism (PCR-RFLP) was taken to genotype rs28665122 (G-105A) and rs34713741 (G-254A) within the SelS gene. The differences in the genotypic distribution between gastric cancer patients and healthy controls were analyzed with the Chi-square test for trends. Logistic-regression analysis was used to estimate odds ratios (OR) and 95% confidence intervals (CI), adjusting for age and sex. RESULTS For rs34713741 in SelS, the allele frequencies analysis indicated that the allele frequency of the T was higher in patients than in controls (P=0.001). There were significant differences of genotype frequencies and allele of rs34713741 polymorphism between gastric cancer group and control group (P<0.05). The relative risk of suffering from gastric cancer in T allele was 1.62 times of CC genotype in Hunan Han population (OR=1.62, 95% CI: 1.15~2.29). But there were no differences of genotype frequencies and allele of SelS rs28665122 polymorphism between gastric cancer group and control group. CONCLUSIONS Allele T of SelS rs34713741 polymorphism is significantly associated with an increased risk of gastric cancer in Chinese population.