谷胱苷肽转移酶P1基因多态性和幽门螺杆菌感染的交互作用与胃黏膜肠上皮化生的风险

摘要

目的 探讨谷胱苷肽转移酶P1基因(GSTP1)多态性与不同类型胃黏膜肠上皮化生(IM)的关系,及GSTP1基因多态性与外源性致病因素--幽门螺杆菌(Helicobacter pylori)感染的交互作用,为确定不同类型IM发病风险提供理论依据.方法 共收集病例381例,轻度慢性浅表性胃炎组[CGS(+)]143例,肠上皮化生组(IM)238例.利用ELISA检测H.pylon-IgG抗体;利用HID-AB-pH2.5进行IM分型;利用PCR-RFLP法检测GSTP1不同基因型.结果 以CGS(+)组为对照组,单因素分析显示,IM组携带G等位基因者的比例高于CGS(+)组(P＜0.05);IM组H.pylori阳性率明显高于CGS(+)组(P＜0.01).效应修饰模型分析显示,在IM阶段,GSTP1基因多态性与H.pylori感染存在着明显的正交互作用,经性别年龄调整后的OR值为9.386(95%CI:3.736～23.580),交互作用指数为2.078,归因交互作用百分比为46.36%.在不同类型IM组单因素分析显示,Ⅰ型IM、Ⅱ和Ⅲ型IM H.pylori感染率均显著高于CGS(+)组(P＜0.01);Ⅱ和Ⅲ型IM组G等位基因频率高于CGS(+)组和Ⅰ型IM组(P＜0.01).在此阶段效应修饰模型分析显示,GSTP1基因多态性与H.pylori感染存在着明显的正交互作用,经性别、年龄调整后的OR值为24.487(95%CI:7.731～77.735),交互作用指数为1.844,归因交互作用百分比为43.89%.结论 GSTP1多态性和H.pylori感染分别是IM发生的危险因素,二者的正交互作用使IM,特别是Ⅱ和Ⅲ型肠化生发病风险明显增高.%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%CI:3.736-23.580) 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.