High-risk events of gastric cancer included a history of gastric ulcer, <i>Helicobacter pylori</i> infection, serological atrophic gastritis (serum pepsinogens), hypergastrinemia (serum gastrin-17), and endoscopic findings of atrophic gastritis, gastric polyps, and gastric ulcer. This evidence concerns the gene GAST and chronic atrophic gastritis.