Currently, the only treatment that can successfully control the progression of CML to the BP is tyrosine kinase inhibitors (TKIs) targeting the BCR-ABL1 p210 protein, inducing a significant reduction in the expression of the BCR::ABL1 transcript, referred to as the major or deep molecular response (DMR), in 80–90% of patients [17]. The gene discussed is BCR; the disease is chronic myelogenous leukemia, BCR-ABL1 positive.