EPIYA motif genetic characterization from Helicobacter pylori isolates in distinct geographical regions of Iran

Abstract

Background: This study aimed to determine the current EPIYA motifs of the cagA gene in Helicobacter pylori isolates from patients with gastric disorders, and evaluate the association between these patterns and the clinical outcome of H. pylori infection in different geographical regions of Iran. Materials and Methods: We examined 150 patients with gastrointestinal disorders from the central and eastern regions of Iran. The detection of H. pylori and screening of cagA was performed by polymerase chain reaction (PCR). The pattern of the motifs was determined by PCR followed by sequencing. Results: The overall prevalence of H. pylori was 66.3% in eastern (Mashad) and 50.6% in the central (Isfahan) part of Iran. The frequency of cagA-positive strains in Mashad and Isfahan were 63.4% and 56.7%, respectively. The pattern of EPIYA motif was as follows: 43 (79.6%) ABC, 7 (12.9%) AB, 4 (7.4%) ABCC, and one (1.9%) ABCCC. We also identified a novel EPIYA C sequence motif which showed association with gastric cancer (GC). The relationship between the frequency of specific EPIYA motifs and GC was statistically significant (P < 0.05). Conclusions: This is the first report for the determination of the cagA EPIYA motif of H. pylori in the Northeast and center of Iran. The prevalence of cagA positive H. pylori between the two regions was significant (P = 0.05). All isolates of the H. pylori cagA were western type (ABC). The increase in the number of EPIYA-C repeats was associated with GC (P = 0.01).