Indeed, pegylated IFN-α2 (PEG-IFN-α2, a long-acting form of IFN-α2b) was used as the standard in the treatment of chronic hepatitis C virus infection until it was replaced by antivirals and is still a therapeutic option in mild to moderate chronic hepatitis B [94,95]. The gene discussed is IFNA2; the disease is chronic hepatitis C virus infection.