Here, we investigated tumorigenic effects of combo HBx mutations (A1762T/G1764A, C1653T, T1753C, and T1674G), Ct-HBx, and wild-type (WT) HBx on HCC using the Sleeping Beauty (SB) transposon system to deliver WT-HBx and HBx mutants into the livers of fumarylacetoacetate hydrolase (Fah)-deficient mice. The gene discussed is FAH; the disease is hepatocellular carcinoma.