SETD1B and chronic myelogenous leukemia, BCR-ABL1 positive: Genetic alterations in SETD1B have been linked to poor outcomes in patients with leukemia, including frameshift or nonsense mutations in chronic myeloid leukemia [42] and a missense mutation in the non-catalytic region (Ala889Asp) in chronic lymphoproliferative disorder of natural killer cells [42].