Abbreviations: BMI, Body mass index; ALBI, albumin-bilirubin; HBV, hepatitis type B; HCV, hepatitis type C; DM, diabetes mellitus; NLR, neutrophil-to-lymphocyte ratio; PLT, platelets; Hb, hemoglobin; PT, prothrombin time; AST, aspartate aminotransferase; ALT, alanine aminotransferase; CHE, cholinesterase; Alb, albumin; T-chol, total-cholesterol; PIVKAII, protein induced by vitamin K absence or antagonist-II; AFP, α-fetoprotein; IM, intrahepatic metastasis; Vp, portal vain invasion; SMI, skeletal muscle mass index. The gene discussed is AFP; the disease is hepatitis B virus infection.