ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: Thus, we create miR-142 knockout CML (i.e., miR-142−/−BCR-ABL) mice, which develop BC and die sooner than miR-142 wt CML (i.e., miR-142+/+BCR-ABL) mice, which instead remain in CP CML.