Based on our previous observations [24] and the two new cohorts in this work (Figure 1, discovery cohort 1 and discovery cohort 2), we developed a model based on the coefficients of the patient’s age, sex, and serum PG, H. Pylori IgG, and gastrin G17 levels to discriminate patients at an elevated risk of GC. The gene discussed is GAST; the disease is gastric cancer.