The last known Pyrenean ibex, a wild goat named Celia, died more than two decades ago, the victim of a falling branch. But before she died, scientists managed to biopsy her skin and stash the sample in a freezer. They were already envisioning a future in which cloning might enable geneticists to bring species back to life.
In 2003, they thawed those cells and made a first attempt to clone Celia. Since they didn’t have any living Pyrenean ibex, they had to get creative. They removed genetic material from goat eggs and replaced it with DNA from Celia’s skin cells. After a mild electric shock, the eggs began to divide. The scientists then implanted these embryos into surrogate moms — goats or goat hybrids. This process — known as interspecies cloning — is tricky. One kid made it to term, but he died a few minutes after he was born.
Read the full article at: https://news.cals.wisc.edu/2021/10/07/the-race-to-the-animal-vault-cals-researchers-look-for-ways-to-store-genetic-samples-and-use-cloning-to-revitalize-endangered-and-possibly-extinct-species/