There remains controversy about whether the BCR::ABL related ATR-Chk1 and ATM-p53-Chk2 axis, which is involved in genomic surveillance, is maintained or perturbed in CML; however, a large number of patients who progress to BP by virtue of wild type p53 downregulation might have this genomic surveillance indeed altered [62]. This evidence concerns the gene ATR and chronic myelogenous leukemia, BCR-ABL1 positive.