KMT2D and chronic myelogenous leukemia, BCR-ABL1 positive: In this study, aiming to detect potential markers to predict genetic evolution and development of therapy resistance, we used an exploratory cohort to investigate the expression profile of MLL2/KMT2D and MLL3/KMT2C genes in CML, in different disease stages, including patients showing different responses to therapy with imatinib mesylate.