Dire Wolves and Grey Wolves already share 99% of their DNA, they modified the blood cells from a grey wolf by inserting dire wolf genes. They modified 20 changes using CRISPR-Cas 9, the blood cells were transferred to a grey wolf egg cell that was implanted in a dog. It will never be possible to create an animal that is 100% identical to an extinct species. But they’re also going to do this for Mammoths, Thylacines, Dodo Birds and The Northern White Rhino.