In the case of AML subtype M3 (French–American–British (FAB) classification), a.k.a acute promyelocytic leukemia (APL), deleterious mutation, namely balanced chromosomal translocation between chromosomes 15 and 17 t (15;17) (q24; q21), affects retinoic acid (RA) receptor gene RARα resulting in formation of dominant negative fusion protein PLM-RARA [2]. The gene discussed is RARA; the disease is acute promyelocytic leukemia.