There is a wide variety of adverse effects due to the use of interferon alpha 2a, including flu-like syndrome (unusual tiredness, fever, chills, muscle aches, and joint pain), injection site reaction (redness, pain at the site of injection), proneness to serious infections, new or worsening autoimmune disease5–7, myelosuppression8,9, depression, suicide, suicidal thoughts, and cardiovascular problems10,11 such as hypotension or hypertension, arrhythmia and myocardial infarction. The gene discussed is IFNA2; the disease is major depressive disorder.