Both the protein and mRNA levels of FHIT were significantly higher after eradication of H. pylori than before eradication of H. pylori in patients with H. pylori infection and family histories of gastric cancer (P<0.05; Figs 4 and 5), in patients with H. pylori infection and without family histories of gastric cancer (P<0.05; Figs 4 and 5), or in patients with H. pylori infection (P<0.05; Figs 4 and 5). The gene discussed is FHIT; the disease is Helicobacter pylori infectious disease.