H. pylori infection can cause a variety of gastrointestinal disorders, including gastritis, gastric ulcers, gastric cancer, and duodenal ulcers. The formation of different diseases caused by H. pylori is associated with GPs in both H. pylori and humans, as well as environmental factors. For example, H. pylori strains with cagA gene have a greater ability to cause disease, and the EPIYA (Glu-Pro-Ile-Tyr-Ala) and multimerization (CM) motifs have been reported to contribute to disease progression. The gene types associated with gastric cancer risk in VacA are the s1, m1, and i1 genotypes. In humans, IL-1β-31T+ and IL-1RN*2/*2 of the IL-1 loci increased the risk of gastric cancer. And individuals carrying the TNF-α-308 have an increased risk of gastric cancer.
Fig. 1 Factors influencing H. pylori’s disease potential in the gastric mucosa (Whitmire & Merrell, 2019).