In Group 1, the following interaction between BCR::ABL1 and JAK2 clones were observed at the time of CML occurrence and during the course of the disease: the majority of cases (18/43; 41.86%) showed an opposite growth of the two genomic alterations with BCR::ABL1 decrease under TKI and JAK2 increase. This evidence concerns the gene ABL1 and chronic myelogenous leukemia, BCR-ABL1 positive.