Clonal hematopoiesis in Philadelphia chromosome-negative bone marrow cells of chronic myeloid leukemia patients receiving dasatinib.

A clonal cytogenetic abnormality was observed in Philadelphia chromosome-negative bone marrow cells of 6/27 chronic myeloid leukemia patients (+8 in 4, -7 in 1, and 20q- in 1) with dasatinib-induced remissions. The X-linked human androgen receptor gene assay demonstrated clonality in one additional patient. Single nucleotide polymorphism array analysis revealed somatic uniparental disomy involving chromosome 17(p12-pter) in another patient. The TP53 gene had a 5' splice site deletion of exon 6 that caused alternative splicing, frame shifting and introduction of a premature stop codon. After three years, no patient developed myelodysplastic syndrome or acute myeloid leukemia.