Aim: To compare the distribution of virulence-associated genotypes of Helicobacter pylori (H pylori) in two areas of north China with different gastric cancer risk and furthermore probe into the pathogenicity of the bacterium.
Methods: Gastric biopsies were taken from 355 subjects from Zhuanghe, a high risk area of gastric cancer, and 136 subjects from Shenyang, a low risk area of gastric cancer. A total of 149 H pylori strains isolated from these patients were studied by PCR for differences in the genotypes of cagA, vacA, and iceA.
Results: In patients with high risk for gastric cancer, higher frequencies of vacA s1 or s1m1b genotypes were found as compared to those from the low risk area.
Conclusion: There is significantly different distribution of H pylori genotypes between Zhuanghe and Shenyang areas in north China.