Genetic analysis also provided a map of virus integration sites in HCC, and it has been reported that mutations in TERT, myeloid/lymphoid leukaemia 4 (MLL4), G1/S-specific cyclin-E1 and 1110 (CCNE1 and CCNE1110), histone-lysine N-methyltransferase (KMTB2), and cyclin-A2 (CCNA2) genes were related to HBV- and adeno-associated virus type 2-induced carcinogenesis [26, 27]. Here, CCNA2 is linked to hepatocellular carcinoma.