Scientists have announced the world’s first de-extinction of an animal species, reintroducing the dire wolf back into the environment.
Colossal Biosciences, a genetic engineering company, birthed three dire wolves, naming them Romulus, Remus and Khaleesi in honor of the legendary creature made famous from the HBO hit series Game of Thrones.
However, the white-coated wolf once roamed North and South America during the Pleistocene epoch before vanishing around 12,000 years ago.
The company extracted DNA from fossilized remains, which was combined with the genetic code of a gray wolf, the closest living relative.
Colossal CEO and co-founder Ben Lamm said in a statement: ‘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 team then cloned high-quality cell lines using somatic cell nuclear transfer into donor egg cells, which involves taking the DNA out of the cell from a donor – in this case a body cell.
The embryos were then transferred to a surrogate, which gave birth to the three healthy pups.
The wolves are thriving on a more than 2,000-acre secure expansive ecological preserve in the US.
Scientists have announced the world’s first de-extinction of an animal species, reintroducing the dire wolf back into the environment
Colossal made headlines last month when it created a ‘woolly mouse’ by engineering rodents to grow thick, warm coats using mammoth DNA.
However, the company’s the ultimate goal is to bring the woolly mammoth back from extinctions.
For the dire wolves, scientists extracted ancient DNA from two fossils: a tooth from Sheridan Pit, Ohio, that is around 13,000 years old, and an inner ear bone from American Falls, Idaho, around 72,000 years old.
The DNA was then sequenced and reassembled using Colossal’s novel approach, resulting in a 3.4-fold coverage genome from the tooth and 12.8-fold coverage genome from the inner ear bone.
‘Together, this data provided more than 500x more coverage of the dire wolf genome than was available previously,’ Colossal said.
Dr Beth Shapiro, Colossal’s Chief Science Officer, said: ‘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.’
Based on Colossal’s genomic analysis, the team used gray wolves as the donor species for establishing cell lines.
The team edited 15 extinct dire wolf variants into the donor gray wolf genome, creating dire wolves that express genes that have not been expressed for more than 10,000 years.
Colossal Biosciences, a genetic engineering company, birthed three dire wolves, naming them Romulus (right), Remus (left) and Khaleesi in honor of the legendary creature made famous from the HBO hit series Game of Thrones
Healthy developing embryos were then transferred into surrogates for interspecies gestation. Three pregnancies led to births of the first de-extinct species.
Dr Christopher Mason, a scientific advisor and member of the board of observers for Colossal, said: ‘The de-extinction of the dire wolf and an end-to-end system for de-extinction is transformative and heralds an entirely new era of human stewardship of life.
‘The same technologies that created the dire wolf can directly help save a variety of other endangered animals as well.
‘This is an extraordinary technological leap in genetic engineering efforts for both science and for conservation as well as preservation of life, and a wonderful example of the power of biotechnology to protect species, both extant and extinct.’
