IFNA1 and chronic hepatitis B virus infection: IFN-α and pegylated IFN-α have been approved for the treatment of chronic hepatitis B. IFN- α binds to its receptor (IFN-α/β-receptor, IFNAR) leading to the downstream signaling pathway and result in the expression of various IFN-stimulated genes (ISGs), which have multiple functions including anti-viral, anti-proliferation, anti-tumor, and immunomodulation.