AFP: Alpha-fetoprotein, ALT: Alanine aminotransferase, AST: Aspartate aminotransferase, INR: International normalized ratio, BCLC: Barcelona Clinic Liver Cancer staging system, FIB-4: Fibrosis-4 index, HCC: Hepatocellular carcinoma, HCV: Hepatitis C virus, and FIB4: Fibrosis-4 score. The gene discussed is AFP; the disease is hepatocellular carcinoma.