Acute promyelocytic leukemia (APL) is a subtype of acute myeloid leukemia (AML) that is cytogenetically characterized by the t (15;17) (q24;q21) translocation and gene fusion between the promyelocytic leukemia (PML) and the retinoic acid receptor alpha (RARA). The gene discussed is RARA; the disease is acute myeloid leukemia.