Global reduction of histone H3 K79 methylation has been previously observed in KMT2Ar-AML patients.49 Cases with KMT2A-MLLT3 rearrangements show much better outcome than the KMT2A-MLLT4 and MLLT10 cases represented in MLLGA and are not considered poor risk. This evidence concerns the gene MLLT3 and acute myeloid leukemia.