A species of wolf that died out some 12,500 years ago lives again as the “world’s first successfully de-extincted animal,” according to Colossal Biosciences, a biotech company based in Dallas, Texas, the United States.

Colossal scientists have created three dire wolf pups by using ancient DNA, cloning and gene-editing technology to alter the genes of a gray wolf, the prehistoric dire wolf’s closest living relative, the company announced last week. The result is essentially a hybrid species similar in appearance to its extinct forerunner.

The dire wolf, Aenocyon dirus, which was the inspiration for the fearsome canine featured in the HBO TV series “Game of Thrones,” was a top predator that once roamed North America. Dire wolves were larger in size than gray wolves and “had a slightly wider head, light thick fur and stronger jaw,” the company said.

Colossal has been working toward resurrecting the mammoth, dodo and Tasmanian tiger since 2021, but the company had not previously publicized its work on dire wolves.

“This massive milestone is the first of many coming examples demonstrating that our end-to-end de-extinction technology stack works,” said Ben Lamm, Colossal’s co-founder and CEO. “Our team took DNA from a 13,000-year-old tooth and a 72,000-year-old skull and made healthy dire wolf puppies.”

The three dire wolves are living on an 809-hectare site at an undisclosed location enclosed by 3-meter-tall “zoo-grade” fencing, where they are monitored by security personnel, drones and live camera feeds.

Using ancient DNA extracted from two dire wolf fossils, Colossal’s scientists and collaborators said they were able to assemble two high-quality Aenocyon dirus genomes, or complete sets of genetic information.

The team compared the genomes with those of living canids such as wolves, jackals and foxes to identify the genetic variants for traits specific to dire wolves, such as white coats and longer, thick fur. Dire wolves and gray wolves shared 99.5% of their DNA.

“We aren’t trying to bring something back that’s 100% genetically identical to another species. Our goal with de-extinction is always create functional copies of these extinct species. We were focusing on identifying variants that we knew would lead to one of these key traits,” said Beth Shapiro, Colossal’s chief science officer.

The company then used the information from the genetic analysis to alter gray wolf cells, making 20 edits in 14 genes before cloning the most promising cell lines and transferring them into donor eggs from domestic dogs.

“So we can take these eggs and remove the nucleus, and then insert the nucleus that we’ve edited from that gray wolf cell, and that is what we clone,” Shapiro explained.

Healthy developed embryos were then transferred into domestic dogs that acted as surrogate moms.

Two male dire wolf pups were born on Oct. 1, 2024, while a female pup was born on Jan. 30, 2025, according to Colossal Biosciences. (SD-Agencies)

位于美国德克萨斯州达拉斯的生物技术公司Colossal Biosciences宣布他们成功复活了约1.25万年前灭绝的史前巨狼。该公司上周宣布，科研团队通过提取古代化石DNA，结合克隆和基因编辑技术改造灰狼（恐狼现存最近的近亲）基因，成功培育出三只恐狼幼崽。这种混种生物在外形上与已灭绝的祖先极为相似。

曾作为HBO剧集《权力的游戏》中冰原狼原型的恐狼（学名Aenocyon dirus），曾是横行北美洲的顶级掠食者。恐狼体型较灰狼更大，头部略宽，被毛浅而浓密，颌部力量更强。

Colossal公司自2021年起一直致力于猛犸象、渡渡鸟和袋狼的复活计划，但此前从未公布过恐狼研究项目。“这个重大里程碑首次验证了我们端到端复活技术的可行性，”公司联合创始人兼CEO本·拉姆表示，“团队从1.3万年前的牙齿和7.2万年前的头骨中提取DNA，培育出了健康的恐狼幼崽。”

目前这三只恐狼生活在809公顷的封闭区域内，地点保密，周围设有3米高的“动物园级”围栏，由安保人员、无人机和实时监控系统全天候监护。科研团队通过分析两个恐狼化石提取的古代DNA，成功拼出两套高质量的恐狼全基因组。

研究人员将恐狼基因组与现存犬科动物（如狼、豺、狐狸）进行比对，锁定了决定白色被毛、浓密长毛等恐狼特征的关键基因变异。恐狼与灰狼的DNA相似度达99.5%。

“我们并非要复制100%相同的物种，”首席科学官贝丝·夏皮罗解释，“复活计划的目标是培育功能性替代物种。我们专注于编辑那些决定关键特征的基因变异。”

研究团队根据基因分析结果对灰狼细胞进行改造，在14个基因中完成20处编辑后，对最优细胞序列进行克隆并植入家犬的卵细胞。

夏皮罗进一步说明：“我们将这些卵细胞的细胞核取出，替换为编辑过的灰狼细胞核进行克隆。”发育健康的胚胎随后被植入代孕猎犬体内。

该公司透露，两只雄性恐狼幼崽于2024年10月1日出生，雌性幼崽则于2025年1月30日降生。

(Translated by DeepSeek)