Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm characterized by the BCR::ABL1 rearrangement, usually diagnosed by data of peripheral blood, bone marrow cytology, cytogenetics, and the detection of the BCR:ABL1 rearrangement. This evidence concerns the gene BCR and chronic myelogenous leukemia, BCR-ABL1 positive.