The 'dire wolf' that went extinct 13,000 years ago in the Americas has been restored. The legendary wolf, well-known as a symbol of House Stark that defended the North in the HBO drama 'Game of Thrones', has emerged into reality through the power of life sciences.
If the restoration of the dire wolf is proven to be true, it could bolster projects for reviving extinct animals such as the mammoth, the Tasmanian tiger, and the dodo. Some critics argue that this is not a proper restoration and that even if extinct animals were to be brought back, it would result in a waste of resources that could be used for ecosystem conservation.
◇Restoration of the ancient giant wolf through gene editing
On the 8th, the American biotechnology corporation Colossal Biosciences stated, "We extracted DNA from 13,000-year-old teeth and a 72,000-year-old skull of the dire wolf (scientific name Aenocyon dirus) and successfully birthed healthy wolf puppies." The company claimed this was the world's first revival of an extinct animal.
Of the three wolves revealed by Colossal, two (Romulus and Remus) are male, while one (Khaleesi) is female. The wolves are said to be doing well under the care of 10 full-time staff members in a registered ecological reserve certified by the American Humane Society.
The dire wolf is a canid species that lived on the American continent during the Pleistocene epoch and went extinct 13,000 years ago. It was 25% larger than today's gray wolves, similar to its appearance in the drama 'Game of Thrones'. It is believed to have primarily hunted horses and bison.
The oldest fossils of the dire wolf were discovered in South Dakota and date back 250,000 years. However, according to Colossal's genetic analysis, its origins are much earlier. Genetically, it is suggested that the dire wolf first appeared when two species of ancient canids from the late Miocene, dating back 3.5 to 2.5 million years ago, merged.
Benjamin Lamm, co-founder and CEO of Colossal, noted on the same day, "Our research team is proud," adding, "This incredible achievement shows that our restoration technology is effective." Colossal had previously created the 'Colossal Woolly Mouse', reminiscent of the extinct mammoth, by simultaneously editing seven genes in a mouse last month. While that involved implementing mammoth traits in a mouse, this time they have restored the actual extinct wolf.
◇Extinct animal restoration backed by Paris Hilton
Colossal was established in 2021 based on the gene editing technology of renowned geneticist George Church, a professor at Harvard University. The company has received investments worth billions of won to pursue projects that restore extinct animals, including mammoths, Tasmanian tigers, and dodos. Not only global investment firms but also celebrities like Paris Hilton, great-granddaughter of the Hilton hotel founder, have invested in Colossal's extinct animal restoration.
Professor Church, co-founder of Colossal, has already demonstrated world-class capabilities in the field of cross-species gene editing. He founded a company called eGenesis, where he edited 13 genes in pigs and transplanted organs into monkeys. The idea is to humanize pig organs for implantation in humans. In doing so, he used a gene-editing enzyme complex known as gene scissors to precisely cut the desired genes from the DNA. The same method was applied to the restoration of extinct animals, editing the genes of descendants to match those of their extinct ancestors.
According to DNA analysis conducted by Colossal, the dire wolf shares 99% of its genes with the gray wolf. Differences are found in 80 genes, some of which are known to affect body size in dogs and wolves. Additionally, it possesses genes that manifest a brighter color and thick, dense fur. Colossal believes that reviving this gene could allow them to bring back a giant dire wolf.
This time, Colossal's researchers decided to edit 20 genes in gray wolf cells to transform them into dire wolf gene forms. However, ultimately only 15 were edited, as it was discovered that editing the remaining five genes could induce hearing loss and blindness in wolves.
Following gene editing, the next step is animal cloning. An embryo (fertilized egg) was created using stem cells with dire wolf genes and implanted into the uterus of a female dog acting as a surrogate. As a result, two male and one female wolf that were dire wolf-like were born.
The three wolves exhibit characteristics of the dire wolf. They are 20% larger in size than gray wolves of the same age and have dense, light-colored fur not found in gray wolves. Dr. Beth Shapiro, the Chief Science Officer of Colossal stated, "This is the first successful case of rescuing a wolf from extinction," adding, "We are making functional replicas of beings that once existed."
◇Criticism of resource wastage in creating monsters
Colossal claims that the restoration of extinct species could make modern habitats more resilient to climate change. For instance, it is suggested that mammoths could help maintain the permafrost in Siberia, preventing the release of the greenhouse gas methane.
Scientists are casting a critical eye on Colossal's restoration of extinct animals. Professor Tom Gilbert of the University of Copenhagen in Denmark commented, "It's completely ridiculous," arguing that reintroducing extinct animals into ecosystems that have already dramatically changed would be very difficult.
Scientists are also concerned that restoring extinct species undermines efforts to conserve animals currently facing extinction. They argue that resources allocated for species conservation are being wasted on creating strange animals. Professor Douglas McCauley of the University of California, Santa Barbara, criticized that this would result in "nothing but creating monsters in the laboratory."
References
Colossal Biosciences (2025), https://www.businesswire.com/news/home/20250407444322/en/Colossal-Announces-Worlds-First-De-Extinction-Birth-of-Dire-Wolves