Below, we discuss IFN-α’s role in treatment of the main myeloid malignancies: the myeloproliferative neoplasms (chronic myeloid leukemia (CML), polycythemia vera (PV), essential thrombocythemia (ET), and primary myelofibrosis (PMF), as well as in acute myeloid leukemia (AML) and myelodysplastic syndromes (MDS). The gene discussed is IFNA2; the disease is acute myeloid leukemia.