KMT2D and Increased total leukocyte count: All recipients with Kmt2d knockdown developed AML with neoplastic cells expressing stem and progenitor marker c‐Kit as well as myeloid surface markers CD11b/Gr‐1 (Figure 1F), and peripheral blood smears showing leukocytosis with increased numbers of neutrophils, monocytes, and blasts, except three mice in one hairpin shKmt2d (shKmt2d_#2) who had mixed lineage leukemia (Figure 1G).