Using the genomic DNA of 91 patients with CML collected at the time of diagnosis and at other time points, Roche-Lestienne et al. examined four cancer genes, TET2, IDH1, IDH2, and ASXL1, which had been commonly reported in BCR::ABL1-negative hematological cancers. Here, ASXL1 is linked to chronic myelogenous leukemia, BCR-ABL1 positive.