Carrying a 112 bp-segment in Helicobacter pylori dupA may associate with increased risk of duodenal ulcer

The discovery of Helicobacter pylori in 1983 challenged researchers around the world to identify this pathogen's major virulence factors. The main rationale for this kind of research was to identify a biomarker associated with specific diseases following H. pylori colonization. Among different investigated virulence factors, duodenal ulcer promoting gene A (dupA) has been found to be associated with duodenal ulcer (DU), but its effect was different in various geographical regions. To determine the prevalence of dupA, we applied both classic primer pairs and our newly developed primers producing a highly conserved segment in PCR method. In our survey, 143 (47%) H. pylori isolates were obtained from 304H. pylori-colonized individuals [age range of 19–92; 113 (37%) males with the mean age of 50 and 191 (63%) females with the mean age of 49]. The presence of the dupA gene was investigated by using the different specific primers. The prevalence of the 112 bp segment isolated from H. pylori strains recovered from DU, GU and atrophy groups were significantly higher (81%, p value = .002, 64%, p = .065, 68% and p = .047 38%, respectively) than our control group, where the prevalence of the 112 bp segment was only 38%. Interestingly, a significant relationship was observed between the occurrence of DU and the presence of the 112 bp segment [p = .002; OR: 6.98; (95% CI: 1.94–25.00)]. Taken as a whole, we believe the 112 bp region of H. pylori dupA may serve as the first detected biomarker for the early detection of DU in patients admitted to hospitals. •The presence of our conserved region of H. pylori dupA (112 bp seggment) can be used as main candidate for further analysis in the development of DU diagnosis biomarkers.•The present results indicate that there is a relationship between DU disease and existence of 112 bp segment, but not with two classic sequences primary reported by Lu et al. in 2005.