HCV: hepatocellular carcinoma; AFP: alpha-fetoprotein, FIB4: fibrosis 4, APRI: aspartate aminotransferase to platelet ratio index; INR: international normalized ratio; ALT: alanine aminotransferase; AST: aspartate aminotransferase; ANOVA: analysis of variance. The gene discussed is AFP; the disease is hepatocellular carcinoma.