Scientists at the University of Edinburgh's Roslin Institute have developed gene-edited chickens that are partially resistant to bird flu. While the birds are not completely immune, the researchers believe that further changes to their DNA could produce fully immune chickens within three years.
The team identified three genes that are crucial for the bird flu virus to reproduce in the chickens and made two small changes to one of the genes using gene editing. The resulting chickens showed increased resistance to bird flu and had no side effects after two years. However, half of the chickens infected with a high dose of the virus still developed an infection.
This partial resistance may encourage the virus to mutate and pose a risk of another human global pandemic if the intervention were widely used. Nevertheless, the researchers believe that if changes are made to all three genes, a fully resistant bird might be possible. Gene editing involves making precise alterations to DNA to change the function of a gene without harming the organism.
The team is now working to identify further genetic changes required before producing gene-edited chickens for the next phase of research. Bird flu is a significant global threat and has had a devastating impact on both farmed and wild bird populations. In the UK alone, the current outbreak of H5N1 bird flu has caused severe losses in seabird populations and the poultry industry. Critics argue that gene editing only addresses the symptoms of high-density farming rather than the root cause of animal diseases.
Compassion in World Farming (CIWF) expressed concern that gene editing could make it easier to keep animals in poor conditions and called for a restructuring of the poultry sector to reduce stocking densities and flock sizes. However, CIWF supports the use of gene editing to prevent the slaughter of billions of male chicks in the egg industry. Gene editing technology is being used worldwide to develop animals that are resistant to disease and more productive. Legislation has been passed to permit the commercial development and sale of gene-edited food, but a further vote will be required to ensure the animals do not suffer. The study on gene-edited chickens has been published in the journal Nature Communications.