Deshpande et al. (6) showed that, in a transplantation model of murine CALM/AF10+leukemia, the myeloid leukemia cells were frequently B220+, with clonal B cell receptor (BCR) rearrangement and lacked c-Kit expression, demonstrating that these AML cells had lymphoid characteristics. Here, MLLT10 is linked to acute myeloid leukemia.