Harnessing Mitochondrial Mutations to ATAC Clonal Evolution in CLL

In this issue of Cancer Discovery, Penter and colleagues describe the results of applying the recently described technology of combined assay for transposase-accessible chromatin using sequencing and mitochondrial DNA sequencing in single cells from serial samples from nine patients with chronic lymphocytic leukemia. The naturally occurring barcodes, provided by mitochondrial DNA mutations, allowed tracking of subclones with distinct chromatin accessibility profiles and copy-number alterations demonstrating distinct patterns of tumor evolution under a range of selection pressures. See related article by Penter et al., p. 3048.