The mice were created by Colossal Biosciences, which edits DNA for species conservation, and has been working to bring back the woolly mammoth since 2021.
Discussion in Preimplantational Stages of Pregnancy, Ciba Foundation Symposium (edit. by Wolstenholme, G. E. W., and O'Connor, M.), 414 (Churchill Ltd. London, 1965 ...
Relying on CRISPR, they then took both the stem cell and zygote approach to rewriting the mouse’s stem cell to express those traits. The next steps involved more than a little hit and miss.