SETD1B and chronic myelogenous leukemia, BCR-ABL1 positive: The most frequently mutated gene at diagnosis in CP-CML patients (about 10%) is ASXL1; other genes recurrently mutated are IKZF1 mutations and deletions, RUNX1, DNMT3A, KMTD2, SETD1B, TET2, TP53 and JAK2.