Genetic Polymorphisms of CagA and VacA Genes in Helicobacter Pylori Isolates from Chaharmahal and Bakhtiari Province, Iran

Helicobacter pylori is the main cause of various gastroduodenal diseases. The consequences of H. pylori infection may be related to differences in genotype or expression of virulence factors of bacteria as well as host and environmental factors. The aim of this study was to assess cagA/vacA genotypes of H. pylori strains isolated from patients with gastric disorder.

In this cross-sectional study، gastric biopsy specimens were taken from 200 patients with gastroduodenal diseases. The specimens were processed for DNA extraction. The presence of ureC، vacA subtypes، and cagA genes were tested by polymerase chain reaction (PCR). Statistical analyses were performed to investigate the relationships between genotypes and gastric disorders.

Overall، 164 H. pylori strains were isolated from 200 specimens. The frequency of the vacA alleles، sa1/m1a، s1a/m1b، s1a/m2، s1b/m1a، s1b/m1b، s1b/m2، s1c/m1a، s1c/m1b، s1c/m2، s2/m1a، s2/m1b، and s2/m2 were 16. 60%، 4. 30%، 28. 04%، 3. 70%، 2. 50%، 6. 10%، 7. 40%، 2. 50%، 11. 00%، 3. 70%، 0%، and 13. 50%، respectively. The prevalence of cagA gene was 92%. Different alleles of s1/m1 had the strongest relationship with gastric disorders.

Based on our findings، it seems that the presence of cagA gene with vacA s1 genotypes is associated with severe gastric disorders. However، none of studied variables can be considered as an independent marker for the onset of disease.