ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: CMR in CML-CP implies undetectable minimal residual disease (>5-log reduction in BCR::ABL1 transcript level) while deep molecular response (DMR) is operationally defined as a 4-log (MR4; BCR::ABL1/ABL1 ratio on the international scale ≤0.01%) or 4.5-log (MR4.5; ≤0.0032%) reduction in BCR::ABL1 transcript level whereas a 3-log reduction (≤0.1%) is considered major molecular remission (MMR) and a 2-log reduction (≤1%) complete cytogenetic remission (CCyR) [5].