Extinct Dire Wolf Brought Back to Life by US Biotech Firm
Science/Medical/Technology
Thursday 10th, April 2025
3 minute read.
A US biotechnology company has announced the birth of three dire wolf pups, successfully reviving the extinct species using advanced cloning and gene-editing techniques.
Colossal Biosciences, based in Texas, revealed on Monday that its researchers had facilitated the birth of three modern dire wolves, two six month old males named Romulus and Remus, and a three month old female named Khaleesi. The species, which disappeared over 10,000 years ago, gained renewed attention in recent years through its depiction in the television series Game of Thrones.
The breakthrough was achieved using genetic material derived from two ancient samples, a 13,000 year old tooth and a 72,000 year old skull. These were used to reconstruct the dire wolf genome. Blood cells from a living grey wolf, the dire wolf’s closest modern relative, were genetically modified at 20 locations. The edited cells were transferred into egg cells from domestic dogs, which were then implanted into surrogate animals to carry the pregnancies to term.
Colossal’s chief executive, Ben Lamm, described the development as a “massive milestone”.
“I could not be more proud of the team. This massive milestone is the first of many coming examples demonstrating that our end-to-end de-extinction technology stack works”, said Lamm. “Our team took DNA from a 13,000 year old tooth and a 72,000 year old skull and made healthy dire wolf puppies."
Dr Beth Shapiro, the company’s chief science officer, stated, “Our novel approach to iteratively improve our ancient genome in the absence of a perfect reference sets a new standard for paleogenome reconstruction."
“Together with improved approaches to recover ancient DNA, these computational advances allowed us to resolve the evolutionary history of dire wolves and establish the genomic foundation for de-extinction, specifically for selecting with confidence dire wolf specific genetic variants that establish our targets for gene editing.”
Dire wolves are distinguished from their modern counterparts by their thicker, lighter-coloured fur, more muscular jaws, and significantly larger body size. Colossal has stated that the pups will be housed in a secure, continuously monitored ecological preserve certified by the American Humane Society and registered with the United States Department of Agriculture.
The company also revealed that it has cloned four red wolves using blood from wild specimens in the critically endangered red wolf population in the southeastern United States. The aim is to improve genetic diversity within the species’ captive population, which is central to conservation and breeding efforts.
George R.R. Martin, author of the Game of Thrones series and an investor in Colossal, commented on the announcement. “Many people view dire wolves as mythical creatures that only exist in a fantasy world, but in reality, they have a rich history of contributing to the American ecosystem”, he said. “I get the luxury to write about magic, but Ben and Colossal have created magic by bringing these majestic beasts back to our world.”
Colossal Biosciences, based in Texas, revealed on Monday that its researchers had facilitated the birth of three modern dire wolves, two six month old males named Romulus and Remus, and a three month old female named Khaleesi. The species, which disappeared over 10,000 years ago, gained renewed attention in recent years through its depiction in the television series Game of Thrones.
The breakthrough was achieved using genetic material derived from two ancient samples, a 13,000 year old tooth and a 72,000 year old skull. These were used to reconstruct the dire wolf genome. Blood cells from a living grey wolf, the dire wolf’s closest modern relative, were genetically modified at 20 locations. The edited cells were transferred into egg cells from domestic dogs, which were then implanted into surrogate animals to carry the pregnancies to term.
Colossal’s chief executive, Ben Lamm, described the development as a “massive milestone”.
“I could not be more proud of the team. This massive milestone is the first of many coming examples demonstrating that our end-to-end de-extinction technology stack works”, said Lamm. “Our team took DNA from a 13,000 year old tooth and a 72,000 year old skull and made healthy dire wolf puppies."
“It was once said, ‘any sufficiently advanced technology is indistinguishable from magic’. Today, our team gets to unveil some of the magic they are working on and its broader impact on conservation.”
Dr Beth Shapiro, the company’s chief science officer, stated, “Our novel approach to iteratively improve our ancient genome in the absence of a perfect reference sets a new standard for paleogenome reconstruction."
“Together with improved approaches to recover ancient DNA, these computational advances allowed us to resolve the evolutionary history of dire wolves and establish the genomic foundation for de-extinction, specifically for selecting with confidence dire wolf specific genetic variants that establish our targets for gene editing.”
Dire wolves are distinguished from their modern counterparts by their thicker, lighter-coloured fur, more muscular jaws, and significantly larger body size. Colossal has stated that the pups will be housed in a secure, continuously monitored ecological preserve certified by the American Humane Society and registered with the United States Department of Agriculture.
The company also revealed that it has cloned four red wolves using blood from wild specimens in the critically endangered red wolf population in the southeastern United States. The aim is to improve genetic diversity within the species’ captive population, which is central to conservation and breeding efforts.
George R.R. Martin, author of the Game of Thrones series and an investor in Colossal, commented on the announcement. “Many people view dire wolves as mythical creatures that only exist in a fantasy world, but in reality, they have a rich history of contributing to the American ecosystem”, he said. “I get the luxury to write about magic, but Ben and Colossal have created magic by bringing these majestic beasts back to our world.”
