Acute promyelocytic leukemia (APL) is a unique subtype of acute myeloid leukemia (AML) characterized by coagulopathy and the accumulation of morphologically aberrant promyelocytes carrying one of the rearrangements involving the RARAα gene, which encodes the retinoic acid receptor alpha located at 17q21. This evidence concerns the gene RARA and acute myeloid leukemia.