Prevalence of cagA, cagT, cagE, vacA and hrgA genes in Helicobacter pylori strains isolated from patients with gastric cancer in Karaj city, 2016

Background: It is estimated that approximately half of the planet's population is infected with Helicobacter pylori and 70%-60% of the infections in the Western countries are caused by cagA-positive strains. The aim of this study was to determine the frequency of cagA, cagT, cagE, vacA and hrgA genes in H. pylori isolated from patients with gastric cancer. Materials and Methods: A total of 50 non-repetitive biopsy samples were collected from patients undergoing endoscopy in the endoscopic center of the Shahid Fayaz Hospital in Karaj. The presence of cagA, cagT, cagE, vacA and hrgA genes was determined using the multiplex PCR method. Results: Of the 50 gastric biopsies, 44 samples (88%) were positive for the presence of various virulence genes. The molecular analysis of virulence factors showed that the prevalence rates of cagA, cagT, cagE, vacA and hrgA genes were 16 (32%), 8 (16%), 13 (26%), 7 (14%) and 17 (34%), respectively. There was a significant relationship between sex, smoking and gastric ulcer with some genes, but no significant relationship was found between the family history and age group with any of the genes. Conclusion: The presence of various pathogenic genes has a significant effect on gastric ulcer, duodenal ulcer and gastric cancer. The effects of other genes, such as hrgA, are important in tissue damage and inflammatory responses