Treg immunosuppressive activity in HBV and HCV infection has dual consequences on the disease prognosis by i) restraining the CD8+ and CD4+ T cell activity which is beneficial for the host since it prevents the inflammatory liver damage and ii) persisting the infection since it provides protection for the virus from the immunogenic activities of CD8+ and CD4+ T cells (95, 96). The gene discussed is CD8A; the disease is infection.