‘Good lord, this thing is huge’: Pups bred using DNA from extinct dire wolf

Three genetically engineered wolves bred using DNA from extinct dire wolves are trotting, sleeping and howling in an undisclosed secure location in the US, according to a company that aims to bring back lost species via de-extinction.

The wolf pups, ranging in age from three to six months, have long white hair and muscular jaws, and already weigh about 36 kilograms – on track to reach 63 kilograms at maturity – about 20 to 25 per cent bigger than their closest living relatives, researchers at Colossal Biosciences said.

Dire wolves, which became extinct more than 12,000 years ago, were much larger than today’s grey wolves.

A photo provided by Colossal Biosciences of genetically engineered pups Romulus and Remus.Credit: AP

The scientists learnt about specific traits that dire wolves possessed by examining ancient DNA from fossils. The researchers studied a 13,000-year-old dire wolf tooth unearthed in Ohio and a 72,000-year-old skull fragment found in Idaho, both part of natural history museum collections.

Then the scientists took blood cells from a living grey wolf and used gene-editing to genetically modify them in 20 different sites, said Colossal’s chief scientist, Beth Shapiro. They transferred that genetic material to an egg cell from a domestic dog. When ready, embryos were transferred to surrogates, also domestic dogs, and 62 days later the first dire wolf puppy was delivered via caesarean section.

Colossal’s Matt James told Bloomberg he was immediately struck by its size. “Good lord, this thing is huge,” he said as he picked it up.

“I can’t believe we’re holding the first dire wolf in 12,000 years,” he told Bloomberg.

The London Telegraph reported the puppies were two brothers – named Romulus and Remus after the fabled founders of Rome who were supposedly nurtured by a she-wolf – and a younger female pup called Khaleesi, as in the popular Game of Thrones character.

Darya Tourzani, a reproductive biology scientist who worked on the project, told the Telegraph the breakthrough was “science fiction at its finest”.

Colossal describes de-extinction as the “process of generating an organism that both resembles and is genetically similar to an extinct species”.

Jon Snow is reunited with his dire wolf, Ghost, in the Game of Thrones finale. Credit: HBO

Independent scientists said this latest effort did not mean dire wolves were coming back to North American grasslands any time soon.

“All you can do now is make something look superficially like something else”— not fully revive extinct species, said Vincent Lynch, a biologist at the University at Buffalo who was not involved in the research.

Colossal has previously announced similar projects to genetically alter cells from living species to create animals resembling extinct woolly mammoths, dodos and others. In 2022, it announced plans to bring back the Tasmanian tiger.

Though the new pups may physically resemble young dire wolves, “what they will probably never learn is the finishing move of how to kill a giant elk or a big deer,” because they won’t have opportunities to watch and learn from wild dire wolf parents, said Colossal’s chief animal care expert, Matt James.

One of the pups at 15 days old.

The company also reported today that it had cloned four red wolves using blood drawn from wild wolves of the south-eastern US’s critically endangered red wolf population. The aim is to bring more genetic diversity into the small population of captive red wolves, which scientists are using to breed and help save the species.

Colossal chief scientist Dr Beth Shapiro, co-founder and lead geneticist George Church (centre) and chief executive Ben Lamm.

This technology may have broader application for conservation of other species because it’s less invasive than other techniques to clone animals, said Christopher Preston, a wildlife expert at the University of Montana who was not involved in the research. But it still requires a wild wolf to be sedated for a blood draw and that’s no simple feat, he added.

The company chief executive, Ben Lamm, said the team met with officials from the US Interior Department in late March about the project. Interior Secretary Doug Burgum praised the work on X as a “thrilling new era of scientific wonder” even as outside scientists said there were limitations to restoring the past.

“Whatever ecological function the dire wolf performed before it went extinct, it can’t perform those functions” on today’s existing landscapes, said Lynch.

AP

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