Relationship between single-nucleotide polymorphisms of human protection of telomeres 1 genes and gastric cancer.

Objective To investigate the relationship between single-nucleotide polymorphisms of IVS13-98G/T of human protection of telomeres 1 (hPOT1) genes and gastric cancer. Methods A total of 168 patients with gastric cancer (gastric cancer group) who had been admitted to Wuwei Cancer Hospital, Wuwei People's Hospital and Liangzhou District Hospital from December 2005 to July 2006 and 156 healthy people (control group) were genotyped by polymerase chain reaction (PCR) and PCR-restriction fragment length polymorphism (PCR-RFLP) method, and the relationship between the distribution of genotypes and the risk faetors of gastric cancer was analyzed. The distribution of genotypes and allele frequency between the 2 groups were compared by chi-square test. Hardy-weinberg equilibrium test was adopted to determine whether the distribution of genotypes and allele frequency were representative. Relative risk and 95% confidence interval were calculated by non-conditional Logistic regression model. Results The frequencies of genotypes GG, GT and TT of hPOT1IVS13-98 G/T were 21.4%, 41.7% and 36.9% in gastric cancer group, and 24.4%, 51.9% and 23.7% in control group. The allele frequencies of G- and T-allele were 42.3%, 57.7% in gastric cancer group, and 49.7%, 50.3% in control group. There was no significant difference in allele frequencies of G- and T-allele between the 2 groups (X~2=3.58, P>0.05). Compared with genotype TT, the relative risks for GT and GG were 0.439 (95% CI: 0.251-0.767, P < 0.05) and 0.514 (95 % CI: 0.264-0.999, P=0.05). There was no influence of different genotypes of hPOT1IVS13-98 G/T, sex, smoking history, family history of cancer on gastric cancer. Conclusion Single-nucleotide polymorphisms of IVS13-98G/T of hPOT1 may be a protective factor of gastric cancer. Key words: Gastric neoplasms;  Human protection of telomeres 1 gene;  Single nucleotide polymorphisms