Scientists have created genetically modified chickens that are immune to bird flu

Chickens could soon be manipulated to be resistant to bird flu after British scientists managed to genetically modify a group of birds to become completely resistant to the virus without any serious side effects.

For the first time, gene editing has reduced the risk of influenza infection. Chickens have become fully resistant to bird flu after editing three of their genes.

The success of a technique known as CRISPR/Cas9 in chickens paves the way for a significant reduction in the spread of avian influenza from wild animals to poultry. This in turn will reduce the number of infections in all bird species and perpetuate the virus through transmission between different groups.

And it will also reduce the risk of the virus mutating into a form harmful to humans, since fewer cases of flu mean fewer opportunities for the virus to mutate harmfully.

The avian influenza virus survives in chickens thanks to the ANP32A protein. Scientists immunized chicken against bird flu by changing the gene that makes the protein to limit its production. This provided good but not complete protection. However, editing two related genes known as ANP32B and ANP32E provided complete protection.

“Chickens genetically resistant to bird flu could prevent future outbreaks. Our results show that gene editing is a possible route,” says Alewo Idoko-Ako from the University of Edinburgh.

“Our work illustrates the first experimental step towards producing influenza-resistant chickens,” he said.

However, the researchers stress that further research is needed to ensure the animals’ health is not compromised, suggesting that the use of gene editing will continue for several years.

Genetically modified chickens are created by editing the genes in the “germ cells” of normal adult chickens—the body cells that develop into sperm and eggs. The resulting offspring were then tested for resistance to avian influenza.

Experts in the field who were not involved in the study welcomed the development.

“This is a breakthrough… The study was carried out by a highly respected collaborative team of international scientists and provides important proof of principle for the genetic control of avian influenza – and its transmission between chickens,” said Professor James Wood from the University. Cambridge. .

“The use of genetically modified, disease-resistant chickens in agriculture would be an impressive achievement, and the pyramidal structure of the global poultry industry could ensure the rapid adoption of these flu-resistant chickens in many countries and continents.”

“Avian influenza in commercial poultry has had a huge impact on the economy and human health over the past two decades or more. These results may provide a reliable solution that is not specific to different virus strains, as is the case with vaccines, which are still strain specific.

“However, there are still many detailed considerations, some of which are regulatory in nature in some parts of the world, that need to be addressed before this work will have clear practical benefits,” he added.

An estimated 2.8 million farm birds were killed in the UK last year, including chickens, ducks, turkeys, geese, pigeons, partridges, quail, guinea fowl and pheasants. It is estimated that more than 50,000 wild birds died in the UK between October 2021 and April 2023.

Although poultry vaccines exist, they have not yet been widely used effectively because the influenza virus continues to mutate and vaccinating millions of birds is expensive and impractical.

A government spokesman said in March: “Vaccination of poultry and captive birds against avian influenza, except in approved zoos in England, is not currently permitted.”

“Although there are currently approved vaccines in the UK, they are unlikely to provide complete protection against current strains of the virus – it is likely that some vaccinated birds will still be able to transmit avian influenza if infected.”

“We continue to invest in avian influenza research and the development of effective vaccines to combat this virus.”

Research published in the journal Natural communication It involved researchers from Imperial College London, the University of Edinburgh, the University of Bristol, the Royal Veterinary College London and the Pirbright Institute.