The gene encoding MOZ was initially identified in several recurrent chromosomal translocations, with either CBP, p300, or TIF2/NCOA2 found in a distinct subtype of acute myeloid leukemia (AML) with French–American–British M4/5 morphology characterized by a poor prognosis 2, 7, 8, 9, 10. The gene discussed is EP300; the disease is acute myeloid leukemia.