Gene editing offers protection against bird flu.Credit: Digicomphoto/ SPL /Getty Images
A former veterinarian from Nigeria, Alewo Idoko-Akoh, has played a central role in an international bird flu breakthrough which, by modifying the DNA of chickens, opens the way to end future outbreaks of one of the world’s costliest animal diseases.
Currently a research associate at the School of Biochemistry, Bristol University, United Kingdom, he is among a team of leading geneticists who published the first proof of concept in Nature Communications that genome engineering could successfully restrict the spread of the bird flu virus in live chickens.
A co-lead author on the paper, Idoko-Akoh began studying genome editing in 2015. Four years later, he was instrumental in the establishment of a United Kingdom Research and Innovation (UKRI)-sponsored project to use gene editing technology to develop chickens that are resistant to bird flu.
The paper details how scientists, including from the University of Edinburgh, Imperial College London and the Pirbright Institute, bred chickens in which they had genetically altered the section of DNA that produces the protein ANP32A. This is the molecule that flu viruses “hijack” for replication.
“When the ANP32A gene-edited chickens were exposed to a normal dose of the H9N2-UDL strain of avian influenza virus – commonly known as bird flu – nine out of 10 birds remained uninfected, and there was no spread to other chickens,” the authors said during a press conference ahead of publication.
The team exposed the gene-edited chickens to an artificially high dose of the virus to further test their resilience, and although five of the 10 birds became infected, the gene edit still offered some protection. The amount of virus in these chickens was much lower than would usually be seen in non gene-edited chickens, and there was no onward transmission to gene-edited birds.
Although they achieved almost complete resistance to bird flu, the single gene edit didn’t go far enough, the researchers said. When they edited proteins ANP32B and ANP32E in the laboratory, however, the triple approach successfully blocked growth of the virus.
“Gene-editing offers a promising route towards permanent disease resistance, which could be passed down through generations, protecting poultry and reducing the risks to humans and wild birds,” said co-lead author Mike McGrew, from the University of Edinburgh’s Roslin Institute. He added that the next step will be to develop chickens with edits to all three genes.
Idoko-Akoh described their method as “safe and robust”, adding that the health of the chickens was also not negatively impacted. As such, it was “an important tool in the toolbox” to address disease outbreaks in livestock populations, including in African countries, he said.
Given the controversial history of genetically-modified crops in Africa, he added that the cultural acceptability of gene-edited chickens could not be ignored. “It is not enough to just develop the technology. It must be done in such a way that it is culturally sensitive and acceptable,” he said.
Future accessibility and affordability would also be crucial. “We are still in the very early stages, but the economic benefits for farmers in Nigeria and other low- and middle-income countries are potentially enormous. We have to think hard about how to ensure that everyone can benefit,” Idoko-Akoh said.
