Interferon (IFN)-α is the main pharmacological treatment for chronic hepatitis C virus (HCV) infection, because of its potent antiviral, antiproliferation and immunomodulatory properties (Lamers et al. 2012); however, at the same time IFN-α is known to induce several neuropsychiatric side effects, including anorexia, fatigue, lethargy, loss of interest, lack of concentration, irritability, cognitive decline, emotional lability and social withdrawal (Cattie et al. 2014). The gene discussed is IFNA2; the disease is Mental deterioration.