A United Nations report published last month painted a stark picture of global biodiversity loss. It estimates that more than 1 million species are at risk of extinction, many within decades, due to farming, logging and other human activities.

Conservationists have restored some species, such as the southern white rhino and American bison, but the risk of extinction for birds, mammals, amphibians and corals shows little sign of decreasing.

Researchers are now asking whether genetic engineering could help protect endangered species. It may sound like science fiction, but scientists at North Carolina State University — and around the world — are exploring ways to use the technology for conservation.

Potential applications include a wide range of interventions, from eradicating invasive rodents on islands to boosting the resilience of American chestnut trees against destructive fungi.

“New tools for gene editing and strategies such as synthetic gene drives open opportunities for imagining ways we might ‘engineer’ biology beyond laboratories and agricultural fields,” said Jason Delborne, an associate professor in the Department of Forestry and Environmental Resources in the College of Natural Resources.

“The conservation community is starting to wrestle with whether and how these technologies could be applied to complex environmental problems,” he added. 

Delborne, who leads research in the Genetic Engineering and Society Center at NC State, studies interactions among policymakers, scientists and the public. He is a member of the IUCN Task Force on Synthetic Biology and Biodiversity Conservation, which recently published an assessment of genetic engineering for conservation.

A New Tool for Conservation

Genetic engineering allows scientists to manipulate an organism’s DNA. They can remove a gene from one organism and insert it into another, giving the recipient new traits.

Humans have been manipulating life for thousands of years through selective breeding, choosing organisms with desirable traits and breeding them in hopes their offspring inherit those traits. Dogs, domesticated from Eurasian gray wolves at least 15,000 years ago, are one of the best-known examples.

By the mid-20th century, genetic engineering emerged as a distinct field of science. Researchers mapped DNA and developed ways to manipulate it. Today, technologies such as CRISPR allow precise edits to DNA, and gene drives could theoretically spread changes through wild populations.

Gene drives are tiny snippets of DNA that have been tweaked by scientists to alter the way that certain genes, and therefore traits, are inherited. Normally, a gene has a 50-50 chance of passing from parent to offspring. Gene drives can raise that probability above 95%, potentially changing an entire population over a few generations.

Some conservationists are exploring gene drives to protect threatened or endangered species. Delborne is working with an international consortium of scientists, including several other NC State researchers, to study the use of gene drives to eliminate invasive rodents on oceanic islands.

Brought aboard ships in the 19th century, these rodents devastate island ecosystems by preying on ground-nesting seabirds and their eggs, many of which are endangered.

The consortium, called the Genetic Biocontrol of Invasive Rodents program, is exploring whether releasing modified mice could crash invasive populations. The mice would carry a gene drive that produces only male offspring, eventually reducing the population over several generations. The technology is still years from field deployment.

Promises and Perils

Gene drives could help protect endangered species, but there’s no guarantee they will work in the wild, Delborne said. This has left both the public and the scientific community cautious about their use and the potential impacts they might have on nature.

One concern is containment. Modified organisms could spread beyond the intended area, affecting other species and ecosystems. Rodents, for example, are invasive on some islands but play critical roles in other ecosystems.

Genetic engineering could also impact local economies, cultures and indigenous communities. Regulatory and ethical uncertainties add to the complexity, according to Delborne.

“Genetic engineering has potential, but every intervention carries risks,” he said. “We have to consider the impacts of these technologies and how they compare to other tools.”

Delborne added, “We also have to ask how much we care about these problems and whether we’re willing to take risks. Protecting a species isn’t just about biology; it changes how we interact with the natural world.”

The IUCN Task Force on Synthetic Biology and Biodiversity Conservation recommends keeping gene drive research in controlled settings until scientists understand how it behaves in the wild. Deployment should be based on case-by-case risk and benefit assessments, guided by empirical evidence and informed by ethical and cultural considerations.

The group also calls for stronger collaboration among scientists and conservationists, and for obtaining informed consent from local and indigenous communities before introducing gene drives.

As part of the task force’s work, Delborne leads workshops and stakeholder engagement efforts, involving scientists, the public and indigenous communities in conversations about gene drive mice and genetically engineered American chestnut trees.

“I think one of the worst things we can do is conduct testing behind closed doors and then expect the public to trust us,” Delborne said. “It’s much more promising to be transparent and involve stakeholders throughout the process.”

The task force’s assessment will inform a new IUCN policy on synthetic biology and engineered gene drives, which will be voted on during the World Conservation Congress in June 2020. While not legally binding, the policy will provide a framework for governments, researchers and conservationists in making decisions about these technologies.