The Bcr-abl fusion gene encodes a pathogenic protein (p210BCR-ABL) that continuously increases tyrosine kinase activity and activates multiple downstream signaling pathways to promote the occurrence and development of myeloid leukemia (chronic myeloid leukemia, CML) [25–27]. The gene discussed is BCR; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.