DNA Typewriter and PEtracer reconstruct cellular family trees in mouse embryos
Published in Bioinformatics, Biology, Journals, Tools.
October 9, 2026. Two teams have reported DNA-recording approaches that reconstruct cellular ancestry during mouse embryonic development. UW Medicine announced on October 8 that its DNA Typewriter study was published in Science that day; Max Planck researchers separately highlighted a PEtracer study in Cell.
DNA Typewriter uses sequential genetic marks to preserve a record of ancestry. Researchers reconstructed a lineage tree covering approximately 1.3 million cells from one embryo, from the fertilized egg through 13.5 days of development. The record connects cellular relationships with gene-expression measurements.
PEtracer uses prime editing at more than 100 genomic sites. Reading inherited marks alongside single-cell sequencing lets researchers connect a cell’s developmental history with its eventual identity.
These tools could help investigate tissue formation, developmental disruptions and cancer evolution. They are experimental lineage-mapping methods in mice, rather than treatments or complete maps of human development. Recording and reconstructing ancestry also differs from continuously observing every cell division.
Sources: UW Medicine announcement, October 8, 2026; Science study; Max Planck announcement, October 8, 2026.