Imagine tweaking the DNA of Hawaiian songbirds so they no longer die from the avianmalaria that has wiped out half of the islands’ native bird species. Or altering the genes of amphibians, so they can shrug off the fungus that has caused the extinction of 90 species.
What are genetically-modified animals?
Genetic modification (GM) is the process of altering an organism’s DNA to give it new features. We already have GM crops. Researchers use GM to create new medicines. Now conservationists are wondering if the same methods could be used to help to save endangered species.
At the recent International Union for Conservation of Nature (IUCN) 2025 World Conservation Congress in Abu Dhabi, members voted to determine whether this should be allowed. Specifically, they voted on two opposing motions.
The first paves the way for research into GM wildlife to proceed cautiously, with all future work carefully considered on a case by case basis. This motion was approved. The second called for a moratorium on genetically engineering wild species in natural ecosystems. This was rejected.
The vote comes at a time when biodiversity is nosediving, and extinction rates are soaring. Conservationists are painfully aware that traditional methods, such as habitat restoration and anti-poaching strategies, are not enough. New methods are needed.
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How could GM and related technologies help species?
GM and related technologies, known collectively as ‘synthetic biology’, could be useful. “Synthetic biology technology is advancing, and in turn its potential implications for nature conservation are growing,” says Thomas Brooks, Chief Scientist at the IUCN.
Disease-resistant animals are one option, but so are corals engineered to survive the world’s warming waters. Scientists have made bacteria that can break down plastic waste. Lab-made versions of natural tissues have been produced. This includes synthetic rhino horn, which could ease the demand for genuine rhino horn, and a lab-made alternative to horseshoe crab blood, which is currently harvested from live animals and used in drug testing.
The technology, however, is divisive. Critics worry that these high-tech methods could backfire. There could be unintended consequences that harm animals, damage ecosystems ormake the biodiversity crisis worse.
In particular, they are worried about a new technology called gene drive. Unlike standard GM methods, gene drives could be used to quickly alter the DNA of entire populations of animals. Researchers have talked about using gene drives to spread positive characteristics, such as disease resistance, but they’ve also talked about using them to wipe out invasive species.
Possums, for example, are native to Australia, but invasive to New Zealand. By targeting genes that reduce fertility, gene drives could be used to exterminate the invasive possums, but what would happen if one of those animals found its way to Australia? The much-loved Ozzy possums could be in danger.
“The outcomes are highly uncertain and complex,” says Guy Reeves, who is an expert on gene drives and Scientific Advisor at the German conservation organisation, Deutscher Naturschutzring.
The results of the votes in Abu Dhabi recognise the need for extreme caution, balanced against the need for innovation. The IUCN is neither for nor against GM wild species, but its newly devised global policy, established at the conference, provides a mechanism to guide how, when, and under what conditions GM wildlife might be approved and introduced.
Revive and Restore is a US-based non-profit that aims to use genetic methods to rescue endangered and extinct species. They are working to ‘de-extinct’ the passenger pigeon and have used cell-based methods to increase levels of genetic diversity in the endangered black-footed ferret. Posting on social media, Revive and Restore described the outcome as a “balanced view of biotech,” adding, “cheers to keeping all options on the table as we continue to innovate for conservation.”
Whilst not legally binding, the new IUCN measures represent the first global policy designed specifically to address the issue of synthetic biology and conservation. As technology progresses, it’s likely that their views will shape the related policies of countries around the world.
