Polymorphism Of CTLA-4 And Helicobacter Pylori Infection On Gastric Cancer Genesis

Objective To analyze the relationship between extron 49 site and promoter 1661 in CTLA-4 gene polymorphism and infection of Helicobacter in Qingdao area and susceptibility to gastric cancer genesis. Methods Polymerase chain restriction fragment length polymorphism and direct sequencing were performed to analyze the genotype of the A/G polymorphism in 49 site、1661 site and 1772 site region, and Hp was detected by pathological diagnosis。Results①he frequency of AG and GG genotype in 49 site were higher in the gastric cancer group compared to the control group (P<0.05)。The frequency of AG+GG genotype in 1661 site was higher in the gastric cancer group compared to the control group(P=0.01), moreover, individuals with the CTLA-4-1661AG+GG genotype rose to 2.63 fold risk for gastric cancer. The frequency of all genotype at point 1772 was not significantly different between gastric cancer group and control group。②In 49 site, Compared with CTLA-4 the AA genotype and the H. pylori negative individuals, there was an increased risk of developing gastric cancer for those carrying GG genotype and H. pylori positive individuals, with 9.56 fold risk.③In 1661 site, Compared with CTLA-4 the AA genotype and the H. pylori negative individuals, there was an increased risk of developing gastric cancer for those carrying AG+GG genotype and H. pylori positive individuals, with 4.04 fold risk. Conclusion There was a relationship between CTLA-4+49 A/G and 1661 A/G polymorphism and susceptibility to gastric cancer.