Moreover, certain mutations can guide tailored targeted therapy and serve as a prognostic factor. Genetic mutations in SETBP1, ASXL1, N/KRAS, SRSF2, and TET2 can be identified in more than 20% of aCML cases [4,16,17]. The gene discussed is KRAS; the disease is atypical chronic myeloid leukemia, BCR-ABL1 negative.