Taken together, our data demonstrated that CRKL (but not CRKII) and miR‐429 contribute to development, progression and erythropoiesis of CML, miR‐429‐CRKL axis regulates erythropoiesis of K562 cells via Raf/MEK/ERK pathway, providing novel insights into effective diagnosis and therapy for CML patients. This evidence concerns the gene MAP2K7 and chronic myelogenous leukemia, BCR-ABL1 positive.