Helicobacter pylori vacA allelic combination, dupA, cagE and cagA genotypes and their associations with gastric diseases among Moroccan population.

The combination of the four regions of vacA with cagA, cagE, dupA genes and cagA-EPIYA motifs, was studied to find the most likely combination that can be used as a disease determinant marker in Moroccan population. A total of 838 H. pylori positive obtained from consenting patients, that were previously analyzed by PCR to characterize vacA-s -m, -i regions, cagE status and cagA 3' region polymorphism, were used to characterize vacA-d region and to determine dupA gene status. The analysis shows the predominance of the less virulent combination (vacA(s2m2i2d2)dupA(-)cagE(-)cagA(-)), and shows that the risk of gastric cancer is 13.33 fold higher (1.06-166.37)) in patients infected by strains harboring vacA(s1m1i1d1)dupA(-)cagE(+)cagA(2EPIYA-C) compared to patients with gastritis without lesions and infected by H.pylori strains harboring vacA(s2m2i2d2)dupA(-)cagE(-)cagA(-). The infection with strains harboring vacA(s1m1i1d1)dupA(+)cagE(+)cagA(1EPIYAC) genotype combination represents a risk factor for gastric ulcer and duodenal ulcer (the Odds Ratio (95% CI) were 16 (1.09-234.24) and 6.54 (1.60-26.69) respectively) compared to patients with gastritis without lesions. These results suggest that the combination of the active form of vacA genotypes, dupA gene status and the number of EPIYA-C motif may be considered helpful markers to discriminate between several gastric diseases.

CagE, cagA and cagA 3' region polymorphism of Helicobacter pylori and their association with the intra-gastric diseases in Moroccan population.

Helicobacter pylori infection is the most important etiological factor in gastroduodenal diseases development. Its evolution is influenced by several factors, including bacterial virulence genes such as cagA and cagE. This work aimed to evaluate the predictive value of cagE alone and in combination with cagA and CagA-EPIYA-C motifs number as a marker of the infection evolution. A total of 823 H. pylori DNA extracted from biopsies of consenting patients suffering from gastritis, peptic ulcer, or gastric cancer. The cagE, cagA status and cagA 3' region polymorphism were determined by PCR. The analysis shows that the risk of duodenal ulcer is 1.97-fold higher (CI = 1.18-3.30) in patients infected by strains cagA+/cagE+. And the risk of gastric cancer is 5.19-fold higher (CI = 1.18-22.70) in patients harboring strains cagE+/2EPIYA-C. The results suggest that cagE in combination with cagA-EPIYA-C motifs number can be used as predictive biomarker of H. pylori infection evolution.