KMT2A and acute lymphoblastic leukemia: We next compared the PTK gene expression profiles of leukemic cells from each KMT2A/MLL-R+ subset to the PTK gene expression profiles of leukemic cells without KMT2A/MLL rearrangements from the corresponding control ALL patients in the “other” categories (Infants, N = 17; Children, N = 94; Adults, N = 131).