The tendency to develop gastric cancer is certainly influenced by polymorphisms of genes involved in inflammatory processes, including a pleiotropic proinflammatory cytokine IL-1β and IL-1RN, TNF-α, IL-8, IL-10, proinflammatory cyclooxygenase enzymes (COX), modulation of acids secretions, generation of oxidative stress, immune response to H.pylori, modification of the barrier function of apical-junctional complexes, as well as regulation of the apoptosis process. The gene discussed is TNF; the disease is gastric cancer.