Chromatin accessibility in leukemia: mapping and the limits of reprogramming

In a recent study published in Nature, Ochi et al. used ATAC-seq to profile bone marrow or peripheral blood tumor cells from 1563 newly diagnosed cases of acute myeloid leukemia (AML), resolving the disease into 16 chromatin-accessibility subgroups (the eCHROMA study) with independent prognostic and pharmacological value, most of them invisible to current genetic classification. 1 This chromatin-based framework raises a sharper question: how much of that architecture can actually be engineered by drugs designed to rewrite it?