Pigs engineered to resist a costly livestock disease have received approval from the U.S. Food and Drug Administration, making them one of the first gene-edited animals cleared for the American food supply. Developed by British biotechnology firm Genus, the pigs have been genetically modified using CRISPR to block the effects of porcine reproductive and respiratory syndrome (PRRS), a virus that has long plagued factory farms. The decision marks a significant milestone for gene-editing technology in agriculture.
A Technological Breakthrough in Livestock Health
PRRS is a major concern for commercial pig farms, especially in the United States, where the virus contributes to the deaths of piglets and causes hundreds of millions of dollars in annual losses. Genus, through its subsidiary Pig Improvement Company, used CRISPR to alter pig embryos and eliminate the cellular receptor that PRRS uses to infect pigs. Without the receptor, the virus cannot enter cells and establish an infection.
According to Matt Culbertson, chief operating officer at the Pig Improvement Company, the edited pigs are immune to more than 99 percent of known PRRS variants. Only one rare subtype of the virus may still pose a threat. Culbertson says the project represents a scientifically rigorous and commercially promising application of gene editing, one that could improve animal welfare and reduce economic losses for producers.
The FDA’s decision comes at a time when regulations around gene-edited animals are gradually easing. Unlike transgenic modifications, which introduce DNA from other species, gene editing modifies the animal’s own genetic material. This distinction has helped position gene-edited organisms more favorably with regulators, especially when the result mirrors traits that could occur through natural mutation or selective breeding.
Comparisons to Other Gene-Editing Efforts
The Genus pigs are among a very limited number of genetically modified animals to enter the human food chain. One earlier example, a fast-growing salmon created by AquaBounty using a gene from another fish species, took nearly two decades to receive U.S. approval. Despite that eventual clearance, AquaBounty recently wound down its operations and sold its fish farms, citing poor commercial performance.
Gene editing has garnered attention for its potential, but also for controversy. The scientific technique used in the Genus pigs is similar to that applied in the 2018 case of gene-edited human embryos in China. In that instance, a scientist edited the genomes of twin girls to make them resistant to HIV by removing a receptor gene. The experiment was widely condemned, but ethical concerns around gene editing in livestock are typically less intense, particularly when the modifications promise clear health or economic benefits.
In the case of PRRS, the benefits could be substantial. Estimates place the annual cost of the virus at over $300 million in the U.S. alone. Globally, pigs account for more than one-third of all meat consumption, second only to poultry. With more than one billion pigs raised each year—half of them in China—disease resistance has significant implications for food security, economic efficiency, and animal health.
Market Impact and Future Prospects
Following FDA approval, Genus now plans to seek regulatory clearance in other key pork export markets, including Mexico, Canada, Japan, and China. Gaining approval in those countries will be essential before the company can fully commercialize its gene-edited pigs for international trade. The company has indicated that it expects gene-edited pork to appear in the U.S. market as early as next year.
Despite the groundbreaking nature of the development, Genus does not expect the meat to carry a bioengineering label. “We aren’t aware of any labeling requirement,” Culbertson said, suggesting that the product may enter the supply chain without specific consumer-facing disclosures. Labeling of genetically modified organisms (GMOs) remains a complex and evolving area in food regulation, with rules varying widely by jurisdiction.
The approval had an immediate financial impact. Following the announcement, Genus saw a significant rise in its market valuation, gaining several hundred million dollars in share value on the London Stock Exchange. Analysts view the development as a potential turning point for the commercial viability of gene-edited livestock, a field that until now has been defined more by scientific promise than market-ready products.
While projects involving glow-in-the-dark animals and other speculative uses of genetic engineering have made headlines, efforts like the PRRS-resistant pig underscore the practical potential of gene editing in addressing longstanding challenges in agriculture. Research is already underway to engineer resistance to other livestock diseases, such as African swine fever and avian influenza—pathogens that, unlike PRRS, can pose risks to human health.