In a preprint, researchers introduced HiDenSeq, a DNA-barcoded Luria-Delbrück assay that uses deep sequencing to track rare adaptation events. Mismatch-repair mutants changed the distribution’s scale, not its shape, indicating a mutator effect. A UV pulse added a distinct mode above spontaneous change.
The method could help scientists study adaptation in microbes and cancers, where rare mutations are hard to observe. By reading patterns across many DNA-labeled cells, researchers can compare mutation-driven change with short-lived plasticity and estimate how much each mechanism contributes.
✦ A population’s adaptation pattern can reveal the mechanism behind it.