Porcine Reproductive and Respiratory Syndrome Virus-Resistant Pigs
In 2023, Health Canada received a submission to allow the sale of gene-edited pigs which are resistant to Porcine Reproductive and Respiratory Syndrome Virus (PRRSV), called PRRSV-resistant pigs.
PRRSV is one of the most significant diseases in commercially raised pigs worldwide. PRRSV causes reproductive issues such as infertility, late-term abortions, stillbirths, and weak piglets. In piglets, PRRSV causes respiratory illness, including difficulty breathing, coughing, fever, poor appetite, tissue damage, lung inflammation, and death. PRRSV also increases pigs’ susceptibility to other infections.
In order to determine whether the pigs could be sold in Canada as food, the scientists at Health Canada conducted a scientific assessment that ensured the pigs are safe for consumption, still have all their nutritional value and therefore do not differ from other pigs available on the market. Our scientists also needed to assess: how the pigs were developed, whether they could be toxic or cause allergic reactions, and the health of the PRRSV-resistant pigs.
The PRRSV-resistant pigs were approved for sale as food in Canada. The science behind the PRRSV-resistant pigs involved the precise deletion of a small part of a pig gene that is involved in infection by PRRSV. This results in pigs which are resistant to infection by PRRSV. In every other way, the PRRSV-resistant pigs are identical to other pigs.
Scientists with expertise in molecular biology, microbiology, toxicology, chemistry, nutrition, and animal biology conducted a thorough analysis of the data and the protocols provided by the applicant to ensure the validity of the results.
Following this assessment, it was determined that the genetic change made to the PRRSV-resistant pigs does not pose a greater risk to human health than pigs currently available on the Canadian market. In addition, Health Canada also concluded that the PRRSV-resistant pigs would have no impact on allergies, that there are no differences in the nutritional value of the PRRSV-resistant pigs compared to other pigs, and that the PRRSV-resistant pigs are as healthy as other pigs.
Health Canada's assessment of the PRRSV-resistant pigs was conducted according to the Codex Alimentarius Guideline for the Conduct of Food Safety Assessment of Foods Derived from Recombinant-DNA Animals. The approach taken by Health Canada in the safety assessment of GM foods is based upon scientific principles developed through expert international consultation over the last 20 years with agencies such as the World Health Organization (WHO), the Food and Agriculture Organization of the United Nations (FAO), and the Organization for Economic Co-operation and Development (OECD). The approach taken by Canada is currently applied by regulatory agencies around the world in countries such as the European Union, Australia/New Zealand, Japan, and the United States.