Research on the interaction between GSTP1 polymorphism and Helicobacter pylori infection in patients with gastric intestinal metaplaisa / 中华流行病学杂志

ABSTRACT

Objective To detect thc distribution ofpolymorphism of GSTP1 and infection rate of Helicobacter pylori (H. Pylori) in different kinds of gastric intestinal metaplasia (IM) and to explore the relationship between entergenic factor-polymorphism of GSTP1 and extogenic factor-H, pylori infection, to determine thc risk of subtype of IM. Methods There were 381 cases in total, including 143 CGS( + ) and 238 IM. H. E. Stain was used for pathological diagnosis. HID-AB-pH2.5 methods were used to classify the IM. ELISA method was used to detect the antibody of H. Pylor-IgG.Polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) were used to analyze the genotype. Results Frequency of G genotype was higher in the IM group, when compared to the CGS ( + ) groups (P＜0.05). The positive rate of H. Pyloriwas statistically higher than CGS( + )(P＜0.01 ). By effect-modified model analysis, GSTP1 gene polymorphsim and H. Pyloriinfection presented a positive interaction in the stage IM,with the OR value as 9.386 (95%CI3.736-23.580) after adjusted by age and gender. The synergy index was 2.078 and the attributable proportion of interaction was 46.36%. The positive rate of H. Pyloriwere statistically bighter than CGS ( + ) group in subtype IM Ⅰ , subtype IM Ⅱ and Ⅲ (P＜0.01). The frequency of G genotype was higher in the IM Ⅱ and Ⅲ group, when compared with the IM Ⅰ groups (P＜0.01). By effectmodified model analysis, in the stage of IM Ⅱ and Ⅲ, GSTP1 gene polymorphsim and H. Pylori infection also presented a positive interaction, with OR value as 24.487 (95%CI 7.731-77.735 )after adjusted by age and gender, with its synergy index as 1.844, and attributable proportion of interaction as 43.89%. Conclusion The infection of H.pyloriand polymorphism GSTP1 gene appeared to be both the external and internal factors, respectively. In the stage of IM, GSTP1 gene polymorphsim and H. Pylori infection also presented a positive interaction, expecially in the IM Ⅱ and Ⅲ.