In order to clarify relationship between these key actors in methylation mechanisms and their potential impact on patient outcomes, we analysed 195 de novo AML patients for the expression of DNMT3A, 3B (and its non-catalytic variant 3BNC) and their correlations with the outcome and the expression of other common prognostic genetic biomarkers (EVI1, NPM1, FLT3ITD/TKD and MLL) in adult AML. The gene discussed is NPM1; the disease is acute myeloid leukemia.