ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive: who found that pathogenic variants in the ABL1 KD were detected in a considerable proportion of adult patients treated with tyrosine kinase inhibitors (TKI),30 the pathogenic somatic SNVs detected in the ABL1 KD in this cohort occurred mainly in paediatric patients with secondary CML‐BP underpinning a particular role of such ABL1 KD variants for blast‐phase transformation under TKI treatment of a preceding chronic phase.