CDKN2B and acute myeloid leukemia: This indicates that the biological impact of p15 hypermethylation on HSC function and differentiation, may only be revealed as cells age in the bone marrow, a clinically relevant finding given our detection of p15 hypermethylation in the peripheral blood of patients with clonal hematopoiesis; a predominantly aging-associated phenomenon with a risk of progressing to AML (27, 46).