KMT2D and acute myeloid leukemia: About 1.6% (3/190) of TCGA AMLs carry KMT2D mutants or deletions.[4] Interestingly, in the OHSU AML cohort (no copy number alteration data), KMT2D mutations (5/531) are all truncating mutations[30] (Figure S2A and Table S1, Supporting Information), suggesting a loss‐of‐function mechanism of KMT2D in AML.