A method for stenciling the structure of individual chromatin fibers onto their composite DNA templates with high precision and resolution is reported by a Harvard Medical School team in Science this week. The technique — called Fiber-seq — uses nonspecific DNA N6-adenine methyltransferases and relies on the ability of single-molecule DNA sequencers to discriminate methylated from unmethylated adenine residues based on the DNA polymerase kinetics at that base during sequencing.