Multivariate logistic regression analysis revealed that male gender (odds ratio: 2.28, 95% confidence interval: 1.11–4.69, p = 0.025) and not using insulin (odds ratio: 0.33, 95% confidence interval: 0.15–0.74, p = 0.007) were independent risk factors for the presence of CGI in the H. pylori-infected patients with T2DM. The gene discussed is INS; the disease is type 2 diabetes mellitus.