Genetic Diversity of Helicobacter pylori Strains Isolated from Patients with Gastroduodenal Diseases Using Multilocus Sequence Typing in Kermanshah

Abstract

Background: Helicobacter pylori bacterium is responsible for gastritis, peptic ulcer, gastric cancer, duodenal ulcer, and mucosal membrane lymphoma. There is a tremendous variety among H. pylori strains. By 2010, ten different populations of H. pylori were identified. The geographical differences between strains may be the explanation for the difference in prevalence of diseases associated with H. pylori in some areas. Various methods have been developed, such as PFGE Southern Blot Analysis-Ribotyping Plasmid Analysis, Rep-PCR and multilocus sequence typing (MLST) for typing H. pylori. Objectives: This study was conducted to investigate the molecular epidemiology and gene variation of H. pylori isolates from patients with gastroduodenal diseases using sequence typing of seventy structural genes. Methods: Two biopsy samples were taken from patients with gastrointestinal disorders. The urease test was performed on one of the samples, the other was cultured on Columbia agar with sheep blood, and then DNA was extracted. Seven structural genes were proliferated with designed primers and then were sequenced. The results were recorded on the MLST and Genbank, as well as the allele numbers and sequence types were determined. Data were analyzed by MEGAv6 and START v2 software. Results: The allele numbers and sequence types of H. pylori strains were unique, and were not recorded previously in the MLST database. The strains of H. pylori isolated from Kermanshah belonged to the hpEurop population. Conclusions: Due to the unique nature of strains and their various sequences, the strains were located in separate clones. Accordingly, none of them could handle the role of type strain in Kermanshah.