Abbreviations: TM, tumor marker; HBs-Ag, hepatitis B surface antigen; HBs-Ab, hepatitis B surface antibody; HCV-Ab, hepatitis C virus antibody; ANA, antinuclear antibody; AMA, antimitochondrial antibody; AFP, alpha-fetoprotein; DCP, des-γ-carboxy prothrombin. The gene discussed is AFP; the disease is neoplasm.