When a snow-white wolf appeared on a recent cover of Time magazine, billed as the resurrection of the fabled and long-extinct dire wolf, the response was swift.
Colossal Biosciences, a Dallas-based US$10 billion (NZ$17.03b) de-extinction company, had succeeded in reconstructing a genome of the dire wolf using ancient DNA from two fossils: a 13,000-year-old tooth and an even older inner ear bone. It had also managed to identify genetic sequences that code for dire wolf traits such as size, musculature and hair colour, and edit these features into the genome of grey wolves.
Some praised the achievement as a breakthrough, but many in the global research community were quick to point out that the three pups born by a surrogate did not signify the resurrection of a species lost to extinction but were merely highly modified grey wolves.
It’s not possible to bring back a species, says University of Canterbury conservation geneticist Tammy Steeves, and even the wider de-extinction community agrees we’ll only ever be able to restore a functional proxy – a hybrid of a living animal with some qualities of a lost species.
Steeves says the more interesting issue is Colossal’s claim to have demonstrated the power of synthetic biology to reshape the future of conservation. The biotech company used similar methods to clone two litters of endangered red wolves to promote its role in saving living species. But its media pack also included a social post by US Department of Interior secretary Doug Burgum celebrating the achievement as proof that “it is not government regulations but innovation that will save species,” at a time the Trump administration is pushing to dial back the protections of the Endangered Species Act.
Even if the technologies were used to save threatened species, Steeves says the scientific challenges remain immense. The Colossal team focused exclusively on traits controlled by a few “big impact” genes, she says. “None of them are related to traits that are of interest to conservation geneticists. These are generally associated with improving reproduction and survival – things that will help a population grow or reverse the decline.”
Regulation of these traits is far more complex, since each is controlled by many genes. Recovering small, inbred populations would require targeting these small impact genes, which are notoriously hard to find. Even if they could be found and edited, the risk of losing the gene edits in subsequent generations would be high without rapid population growth.
Although Colossal is selling its technology as a conservation tool, Steeves says the line being drawn between de-extinction and conservation is at best squiggly. In New Zealand, many now-threatened species once thrived. Populations shrank quickly when habitats changed with the arrival of people and their animals. Once a population is small, genetic diversity is lost randomly, Steeves says, which is why some threatened species are managed intensely to prevent further losses by controlling who breeds with whom.
Gene editing may become an option for conservation here with the expected introduction of new laws, but any future use would be more relevant to work on invasive species rather than threatened ones. Even then, Steeves says, “genetics is but one tool and gene editing is a tiny part of that tool, it is not the saving grace”.
Genomics Aotearoa has described de-extinction as not only impossible but unethical, not least because it diverts resources away from the struggle to save species that are not yet extinct.
But Steeves believes Colossal chose the dire wolf because its pop culture links – from the Grateful Dead song to Game of Thrones − helped attract donors who wouldn’t have invested in saving the red wolf. It allowed the company to show what’s possible. However, she says, as connoisseurs of Jurassic Park pop culture know, just because we can, doesn’t mean we should.
