慢性胃炎、消化性溃疡患者携带株幽门螺杆菌基因分型

Gene typing for Helicobacter pylori isolated from patients with chronic gastritis and peptic ulcer

目的探讨慢性胃炎、消化性溃疡患者携带株幽门螺杆菌(Hp)的基因分型方法。方法对Hp标准株和慢性胃炎、消化性溃疡、非胃炎非溃疡患者携带株基因组DNA进行随机扩增多态性分析(RAPD),PCR扩增空泡毒素基因(vacA)和致病岛基因(cag-PAI)的cagA、cagE、cagT片段,并测定全部菌株的VacA活性。采用聚类分析进行基因分型。结果单纯RAPD分型结果显示不同基因型别Hp与不同疾病结局无关(P=0.0685)。依据vacA+cag-PAI分型结果显示不同基因型别Hp与不同疾病结局无关(P=0.2685)。将RAPD分析结果与vacA+cag-PAI检测结果进行综合聚类,全部菌株可分为3个型别,慢性胃炎、消化性溃疡和非胃炎非溃疡分别有自己的优势基因型,且各型间的总体分布差异有统计学意义(P=0.0067)。VacA的活性表达情况在各基因型之间的分布差异无统计学意义(P=0.2655)。结论Hp基因型与疾病类型有关,空泡毒素基因和致病岛基因可作为Hp基因分型的靶基因,RAPD是有效的基因分型手段。

Aim ： To find a method of gene typing for Helicobacter pylori （ Hp ） and explore the relationship between genotypes of Hp and diseases. Methods：The genome diversity of Hp gene was tested by random amplified polymorphic DNA （RAPD） technology and vacA,cagA,cagE, cagT were amplified by polymerase chain reaction （PCR）. VacA expression was detected using Hela cells cultured with Hp extract. Data were analyzed by cluster method. Results： Neither RAPD nor PCR showed that the genotypes of Hp had relationship with different diseases （ P = 0. 068 5, P = 0. 268 5 ）. However, combining the results of RAPD and PCR, all Hp strains of 3 groups （chronic gastritis group, peptic ulcer group, other disease group） were classified into 3 genotypes. Each group had its own dominant genotype. Statistical significance of genotypes distribution among them was observed （P = 0. 006 7）. VacA expression showed no significant variation among 3 genotypes （P = 0. 265 5）. Conclusion ： It indicates that there is certain relationship between disease types and Hp genotypes, and vacA, cagA, cagE, cagT can be taken as ideal indexes for gene typing for Hp. RAPD is an effective method for genome DNA diversity detection.