Of mice and mammoths (and men)

Colossal Biosciences has taken a significant step in its journey to eventually resurrect the woolly mammoth and play out Ice Age irl.

The de-extinction company yesterday announced the creation of a brand-new species: the “woolly mouse,” or mice genetically modified to have mammoth-like traits geared towards cold tolerance.

How they did it: Colossal researchers started by trying to identify the genes responsible for making mammoths distinctive, comparing ancient samples of mammoths’ genetic material to those from African and Asian elephants (their closest living relative).

• The scientists then tried to activate some of those unique mammoth genes in mice. In particular, they targeted the genes responsible for mammoths’ woolly hair, as well as their way of metabolizing fat that helped them survive in the cold.
• The researchers were able to create healthy mice with the desired woolly hair – though they found no evidence that the fat-increasing gene had any effect.

But…While many outside scientists praised Colossal’s new study, which has yet to be peer-reviewed, they also caution that the company still has a long way to go before they can successfully edit the embryos of Asian elephants to produce woolly mammoths.

• It’s currently unclear whether genetic modifications will be required – or are currently possible – to ensure the animals not only look like mammoths, but behave like them too.

🦣 Zoom out: In addition to its goal of producing the first mammoth-like Asian elephant calves by 2028, Colossal is also working to bring back the dodo bird and the Tasmanian tiger.