To figure out how chromosomes of placental mammals have changed over time, researchers need to know what those early eutherians started with. (sciencemag.org)
The researchers came up with 21 pairs of ancestral eutherian chromosomes, they report today in the Proceedings of the National Academy of Sciences. (sciencemag.org)
So team member Jaebum Kim, now at Konkuk University in Seoul, and colleagues wrote a sophisticated computer program that was able to reconstruct the original eutherian chromosomes based on what parts of the chromosomes are together today in those 19 species. (sciencemag.org)