DOT1L, the only known histone 3 lysine 79 (H3K79) methyltransferase, has been reported to interact with MLL-AF10 [7], and is required for initiation and maintenance of several types of MLL-rearranged leukemias, such as MLL-AF9 and MLL-AF6 [8], [9], [10]. This evidence concerns the gene DOT1L and leukemia.