Much has been made of the potential of genome engineering for “de-extinction”. But what about its potential to help existing threatened species?
In a Perspectives article in Nature Reviews Biodiversity, a team of overseas scientists — including some from the startup behind recent “de-extinction” announcements — examine how genome engineering can be a new tool to add to the conservation toolkit. For example, gene editing could help restore lost genetic diversity to species with small populations. They say it also could help by removing harmful mutations, or introducing new genes from closely related species to confer traits like heat tolerance or disease resistance.
The Science Media Centre asked third-party experts to comment.
Professor Peter Dearden, Director of Genomics Aotearoa, University of Otago, comments:
“This is a good review of the use of gene technologies in conservation, pointing out where gene technologies can play a role, but it is silent on the fact that most of these technologies have never been implemented in the conservation species of interest. Gene editing works well in systems where it has been developed, but developing it in multiple species is going to be hard. Alongside that, the review talks about putting genetic diversity back into the genomes of species with low genetic diversity. This seems optimistic, in that we don’t understand what genetic diversity does even in species that are well studied. Conservation species are never well studied from a genetic point of view, so information as to what variation is ‘good’ and what ‘bad’ is really hard to assess.
“Finally, the cultural context of all of these technologies is really important. These are treasured, rare species. Who makes the decision about whether these manipulations can be done? What are the consequences for the cultural value of these species? The review points out a bunch of useful technologies, but is very quiet about whether ethically, socially, culturally or even biologically, these can be used.”
No conflicts of interest.
Associate Professor Nic Rawlence, Director of the Otago Palaeogenetics Lab, University of Otago, comments:
“Worldwide, genetic engineering is becoming another tool in the conservation tool box that can be used alongside more traditional methods like predator control, habitat restoration, translocation, and genetic rescue (i.e. interbreeding of distinct populations to increase genetic variation) to conserve endangered species. While this technology is still illegal in Aotearoa New Zealand as the current ban has not been lifted, now is the time to be having these conversations as a community, and with mana whenua, over its use, not just on endangered species but also to control predators. The genetic engineering technology that is being developed for ‘de-extinction’ efforts can and should be used for saving species—imagine if we could genetically engineer a species to be resistant to a disease or reintroduce lost genetic variation back into a population to give it the evolutionary potential to adapt to a fast changing world.
“This paper by Cock van Oosterhout and colleagues (including scientists at Colossal Biosciences involved in ‘de-extinction’) is a good start in initiating these conversations, arguing for a measured and cautious approach, with genetic engineering as one tool in the conservation arsenal. There will be challenges to using genetic engineering in endangered species from unintended consequences to the individual, but also the wild populations and ecosystems where these individuals may get released into—it was nice to see a paper that discussed the potential downsides of this technology for a change. While this technology could be a game changer in some situations, it may not be a silver bullet for New Zealand birds, which are characterised by small populations that are slow breeding—this makes getting any new genetic variant (like a disease resistant gene or lost genetic variation) fixed in the population difficult, due to inbreeding (breeding with close relatives) and random loss of genetic variants from generation to generation.
“Where this paper by Cock van Oosterhout and colleagues misses a beat is around discussing Indigenous perspectives and community engagement, which to me feels minimised, and could create the false perception that it’s a ‘nice to have’ but not necessary. In New Zealand, and many other parts of the world, Indigenous and community voices are crucial. There are valid concerns that Māori have been excluded from conversations about using genetic engineering and the draft Gene Technology Bill. Like I raised in my recent Conversation piece, without Māori support or involvement, the genetic engineering of animals and their release would constitute a breach of Article Two of Tiriti of Waitangi (the Treaty of Waitangi). Māori have exclusive rights over taonga species. Māori and many other Indigenous cultures also have whakapapa (genealogical) relationships with plants and animals, and view genetic engineering as unnatural and with disgust, which could have negative consequences for genetically engineered organisms and the environment.
“One aspect of genetic engineering in conservation that not discussed in the paper is its use on pest species, like gene drives where genetic variants that make individuals sterile, for example, are spread throughout a pest population to cause its collapse. Public perception and engagement here will again be crucial. In a study published in Nature Ecology and Evolution in 2017, there was more agreement amongst Department of Conservation staff for the use of this technology to genetically edit pests than endangered species.
“Overall, given recent publicity around genetic engineering and ‘de-extinction’, it’s nice to see a measured approach advocated (including discussing the downsides—you don’t see that with de-extinction) that was not science by press release. In the current environment, funding this potentially revolutionary science will be difficult—the authors were quick to point out, without mentioning de-extinction, that the same private funders could fund this research. If the challenges with this technology can be overcome, then it could be a game changing tool in the conversation toolbox, so long as there was widespread Indigenous and community support, with free, prior and informed consent. Only time will tell, but best to keep up our current conservation initiatives in the meantime.”
No conflicts of interest.
The UK Science Media Centre has also gathered third-party expert comments in response.
Prof Bruce Whitelaw, Professor of Animal Biotechnology and Director of The Roslin Institute, said:
“Biodiversity across our planet is both facing unprecedented challenges and increasing recognised as critical for planetary health. Genome editing technology offers approaches that overcome aspects that current approaches addressing biodiversity cannot address – it can restore lost genetic diversity and increase the resilience of endangered species. Genome editing technology is advancing fast and for species where we know much about their genetic make-up could be used now to reduce genetic load and enable adaption to environmental change. This could include restoration of lost variation but we are still some way-off from restoring a species – although this is foreseeable for the future. No single technology can solve all biodiversity concerns. Genome editing should be adopted alongside traditional conservation methods and habitat restoration. The driver should be for social benefit, have societal involvement, and be guided by science-based regulation – and should be viewed as another useful method in the race to safeguard the world’s needed biodiversity.”
Conflict of interest statement: “I receive funding from BBSRC, Roslin Foundation, and Gates Foundation. I am a member of FSA’s Advisory Committee for Novel Foods & Processes, and the Engineering Biology Responsible Innovation Advisory Panel.”
Prof Dusko Ilic, Professor of Stem Cell Science at King’s College London, said:
“The article is a thoughtful and forward-looking synthesis, offering a powerful vision for integrating genome engineering into conservation biology. However, its weaknesses lie in over-optimism, lack of robust comparative cost-effectiveness analysis, and occasional underplaying of ecological, regulatory, and ethical risks—especially in complex field scenarios.
“The paper persuasively argues that genome engineering can address genomic erosion—an underappreciated long-term threat in conservation biology—by restoring adaptive genetic variation and reducing genetic load. The technology has potential, but the evidence base is currently stronger in theory and in model organisms than in demonstrated success with real-world.
“The authors assume that the relationship between genome-wide variation and fitness is sufficiently understood to justify editing decisions. In reality, the genotype–phenotype–fitness map remains poorly resolved in most non-model organisms, which weakens confidence in editing targets. What improves fitness in captivity or small restored habitats may not translate under fluctuating wild conditions.
“The paper clearly articulates how genome engineering can target fixed deleterious alleles, reintroduce lost immunogenetic diversity, and enhance climate adaptation capacity—things traditional conservation (e.g. protected areas, captive breeding) cannot accomplish once variation is lost.
“The concept is compelling but lacks quantitative modelling or comparative data to support the claim that genome editing is more effective or feasible than scaled-up traditional approaches in most cases.
“The argument presumes that ancestral or heterospecific alleles can be confidently identified and reintroduced without negative pleiotropic effects, but this is rarely tested rigorously outside lab settings.
“The paper is also light on cost-benefit comparisons. For example, how does gene editing for climate resilience compare (in cost, efficacy, and ecological risk) to investing in habitat corridors that allow natural gene flow?
“International approvals for edited wildlife release is a probable limiter of near-term feasibility. Regulatory inertia and public scepticism that have historically limited the rollout of genetically modified (GM) organisms—particularly in agriculture, where decades of commercial GM crop use remain contentious in many countries despite robust safety data. Scientific bodies (e.g., WHO, NAS, EFSA) consistently find no substantiated health risks from approved GM crops, yet public acceptance varies widely. The first GM crop was approved in the US in 1994. Thirty years later, only about 30 countries cultivate GM crops, and about 70 allows imports but not domestic cultivation.
“The distinction between technical readiness (editing) and ecological readiness (release, integration, adaptation) is important. Timescales needed for breeding, backcrossing, release, and population establishment, are equally complex. In species with long generation times, edited lineages may not reach ecological relevance for decades.
“While critical of de-extinction, the authors do not fully confront the blurring of boundaries in practice—e.g. Colossal Biosciences’ projects (which some authors are affiliated with) walk a fine line between de-extinction branding and conservation justification.
“The critique of de-extinction would be more credible if potential conflicts of interest were explicitly addressed, and if more scrutiny were applied to projects that market proxy-species restorations as conservation.
“The call for responsibility is ethically sound, but implementation guidance is vague. How, for example, will conservation scientists ensure openness when working with private-sector collaborators like biotech firms or proprietary genome platforms? How engineered lineages may tie future conservation efforts to specific technologies or patents, raising issues of access, control, and continuity?”
Conflict of interest statement: “I declare no conflict of interest.”
Prof Tony Perry, Head of the Laboratory of Mammalian Molecular Embryology at the University of Bath, said:
“This timely Perspective collates potential contributions from the revolution in ‘genome engineering’ (including genome editing) to biodiversity conservation. The piece points out that to be effective, these advances need to include advanced assisted reproduction methodologies, such as embryonic and stem cell chimeras and nuclear transfer cloning. In addition, the behaviour of individual or small numbers of gene variants moved into a foreign genome may be difficult or impossible to predict, making it desirable to replicate entire genomes from the oldest sources available.
“The challenges of achieving this are considerable even for well-studied species, but by raising the profiles of these challenges, the Perspective promises to accelerate our efforts to solving them for species conservation and its retroactive cousin, de-extinction.”
Conflict of interest statement: “None”