Molecular Characteristics of Caga Gene Epiya Motifs of Helicobacter Pylori Among Patients With Gastroduodenal Diseases

Abstract

Background: cagA gene EPIYA motifs of H. pylori play an important role in the pathogenesis of gastroduodenal disease. This study is aimed at (1) Identify patterns of cagA gene EPIYA motifs ofH. pyloristrains from gastric biopsy specimens; (2) Investigate the association between cagA gene EPIYA motifs and gastroduodenal diseases. Patients and methods: Eighty-nine gastroduodenal disease patients infected with cagA-positive H. pylori were enrolled in this study. The patterns of cagA gene EPIYA motifs were determined by PCR. Result: cagA-positive H. pylori strains with East Asian-type EPIYA motif were predominant (89.9%), whereas strains with Western-type EPIYA motif accounted for only 10.1%. There were two strains with rare East Asian-type EPIYA, as -ABDBD and -AABD. In the duodenal ulcer group, the prevalence of East Asian-type and Western-type EPIYA motifs were 80% and 20%, respectively. Meanwhile, East Asian-type and Westerntype EPIYA motifs accounted for 95.8% and 4.2%, respectively in the gastric cancer group. Conclusion: cagA gene EPIYA motifs of cagA-positive H. pylori were quite diverse with the predominance of East Asian-type EPIYA motif. There were two rare motifs as -ABDBD and -AABD. The frequency of strains with East Asian-type EPIYA motif was highest in the gastric cancer group, whereas it was lowest in the duodenal ulcer group. Key words: Helicobacter pylori, cagA gene, EPIYA motif, gastroduodenal diseases