The M. Lai's group, using a model of in vitro HCV infection of B-cells, showed that the viral infection may induce an enhanced mutation rate of immunoglobulin genes and some oncogenes, possibly through induction of error-prone DNA polymerase and activation-induced cytidine deaminase (AID), suggesting that HCV may cause tumors by a hit-and-run mechanism [42]. Here, AICDA is linked to viral infectious disease.