Role of Plasticity Region Genes and cagE gene of cagPAI of Helicobacter pylori in Development of Gastrointestinal (GI) Diseases

Document Type : Research Articles


1 Department of Biology, Faculty of Sciences, University of MohagheghArdabili, Ardabil

2 Department of Biostatistics, Faculty of Public Health, Mazandaran University of Medical Sciences, Sari, Iran


Background: Helicobacter pylori is a Gram-negative, micro aerophilic bacterium in the human stomach that is associated with the development of gastrointestinal ailments such as peptic ulcer (PU) and gastric cancer (GC). In the present study, plasticity region genes (jhp0940, jhp0945 and jhp0947) and and cagE gene of cagPAI were assessed independently and in combination for their ability to predict clinical consequences. Materials and Methods: A total of 211 strains which were isolated from patients with different gastrointestinal diseases (114 with non-atrophic gastritis, 59 with PU, and 38 with GC) were genotyped by PCR and sequencing. Data were collected and analyzed using SPSS software version 19. Logistic regression models were applied to determine relationships between the plasticity region genes and cagE of H.pylori and clinical status. Results: The cagE gene (71.1%) had the highest frequency and jhp0945 (13.7%) was the least abundant among the genes examined. The jhp0940 gene was significantly associated with GC (P = 0.0007), but not PU. On multiple logistic regression analysis, adjusted for both age and sex, the jhp0940 genotype was significantly associated with GC (odds ratio, OR = 2.8, 95%CI = 1.1–7.0; P = 0.027). The jhp0940+/ jhp0945+/ jhp0947+genotype was also linked to an increased risk of GC (OR = 50.4, 95%CI = 5.1–500.0; P = 0.0008) while no genotype correlation was found with PU in Iran (P > 0.05). Conclusions: Given the high frequency of cagE, this gene could be a suitable marker for the presence of cagPAI in Iranian strains. The jhp0940 genotype could also be a strong predictor of GC in Iran.


Main Subjects

Volume 18, Issue 1
January 2017
Pages 43-49
  • Receive Date: 14 September 2016
  • Revise Date: 13 January 2017
  • Accept Date: 05 February 2017
  • First Publish Date: 05 February 2017