Current evidence suggests that HIV-1 infection modifies the course of HBV with an adverse impact on HBV-related liver disease progression, including higher serum HBV DNA polymerase activity; lower rates of loss of serum hepatitis B e antigen (HBeAg); and increased risk of cirrhosis, liver-related mortality, and hepatocellular carcinoma, especially among patients with lower CD4 cell counts [36, 41–46]. This evidence concerns the gene CD4 and HIV-1 infection.