ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: The current policy of CML therapy with TKI is to achieve a faster major molecular response (MMR or MR3.0 = BCR‐ABL1/ABL1 IS ≤0.1%) to prevent the progression to blastic phase and to obtain a deep molecular response (DMR or MR4.0 if ≤0.01% BCR‐ABL1/ABL1 %IS, or MR4.5 if ≤0.0032% BCR‐ABL1/ABL1 %IS or MR5.0 if ≤0.001 BCR‐ABL1/ABL1 %IS) to gain the opportunity of a treatment discontinuation.5