Both new classification systems have removed the WHO4R entity “AML with mutated RUNX1” as the authors felt this alteration did not define a significantly distinct disease entity given the potential for misclassification of “AML with germline predisposition (RUNX1 mutation)” and the close association with progression from myelodysplastic syndromes (MDS) and prior chemoradiotherapy [3,6,7,8]. This evidence concerns the gene RUNX1 and myelodysplastic syndrome.