Genetic engineering Company breeds wolf with genes from an extinct species
Three young wolves with light-colored fur are being advertised by a US company as resurrected dire wolves. In fact, they are genetically modified gray wolves that carry some of the genes of a species that became extinct around 12,000 years ago.
08.04.2025, 14:12
SDA
Colossal Biosciences, a US company based in Dallas that specializes in such projects, has now presented the hybrids to the public: the males Romus and Remulus, who were born at the beginning of October, and the female Khaleesi, who was born at the end of January.
The company is talking about the first direwolves since the Pleistocene period, which ended around 10,000 years ago. According to the company, the three young animals resemble their extinct "ancestors" of the species Aenocyon dirus, which once lived in North America, with their thick, light-colored fur, larger stature and allegedly also a special howl.
Mice have also been modified
Colossal Biosciences had already caused a stir at the beginning of March with its "woolly mice", genetically modified mice whose fur structure is said to resemble that of woolly mammoths. For the wolves now presented, the company had sequenced genome residues from two dire wolves that lived 13,000 years ago and 72,000 years ago in what is now the USA. By making comparisons with modern-day wolves, the team determined which genetic characteristics were typical of the extinct species.
Finally, they modified the genetic material of gray wolves (Canis lupus) in 20 places in 14 genes accordingly. In total, the genetic material of gray wolves contains around 19,000 genes. The resulting hybrids are therefore much more closely related to the gray wolf than to the dire wolf.
The modified cell nuclei were packed into enucleated egg cells and, according to the company, 45 embryos initially developed. These were implanted into dog mothers. The resulting three young wolves are said to live in an enclosure, the location of which has not been disclosed.
Experts react skeptically
Independent experts are critical of the presentation of the animals. They are only hybrid gray wolves with some possibly direwolf-like characteristics, Nic Rawlence from the University of Otago in New Zealand told the New Zealand Science Media Center (SMC). The zoologist emphasized that the special characteristics actually originated from direwolves was merely an assumption.
"To really resurrect something, you would have to clone it," said Rawlence. "The problem is that we can't clone extinct animals because the DNA is not preserved well enough." Even if the genome is sequenced, the DNA cannot be extracted in sufficiently large pieces, as is possible with a living animal.
It makes much more sense than the company's approach to develop technologies and ways to prevent the extinction of species. In other words, to preserve what we still have.
According to the SMC, Philip Seddon, also from the University of Otago, speaks of amazing technological advances, but: "The cute pups Romulus, Remus and Khaleesi are not direwolves - they are genetically modified gray wolves." The two species are not even closely related, the last common ancestor probably lived around six million years ago.
Company wants to produce mammoths
Colossal Biosciences was co-founded by Harvard researcher George Church, who became internationally famous for his announcement that he wanted to create a cold-resistant elephant that looked like a mammoth and behaved as similarly as possible.
The woolly mice with their golden-yellow shaggy fur presented a month ago were supposed to be a step towards this goal. The mice's genes had been altered so that their hair texture and color somewhat resembled that of mammoths.
