WIDESPREAD use of anti-viral drugs in livestock creates a risk for human health – so agriculture should look instead to genome editing to disease-proof its animals.

This approach has already yielded results in tackling respiratory disease in pigs, and one of the scientists behind that breakthrough, Professor Helen Sang of the Roslin Institute at the University of Edinburgh, is calling for the technology to be fully harnessed as a means of preventing disease spread and drug resistance throughout livestock production.

Prof Sang will be a speaker at the Agri-TechE event ‘Advances in Breeding for Agriculture – New Tools for New Solutions’ on September 23, where a number of advanced breeding techniques will be discussed.

Pointing to the billions of poultry currently being dosed with antiviral drugs as a preventative to bird flu, particularly in China, she explained: “Antiviral drugs that are very similar to those used in human healthcare are a really bad idea for use in farmed animals, as their usage can cause resistance to the drug, which then removes the efficacy of the drug for use in humans if the disease does end up spreading.

“Finding a genetic way, either by conventional breeding or genome editing, to embed the resistance in the genetics can be a good tool for combatting disease.”

Prof Sang's breakthrough targeted Porcine Respiratory and Reproductive Syndrome, which causes breathing problems and deaths in young animals and pregnant sows to lose their litters.

“Vaccines are available for PRRS but are not fully effective, resulting in PRRS being an endemic disease of pigs in the UK, with the consequent economic losses and animal welfare challenges," she said.

But as the PRRS virus binds to a particular protein on the surface of the host pig's cells, genetic engineering at the Roslin Institute was used to edit that protein, denying the virus its foothold.

“Colleagues used CRISPR-Cas9 to chop out part of the protein from the pig’s gene – they showed that the pig is still perfectly healthy and happy, but if you try and infect the pig with PRRS, it just won’t become infected," she reported. "That shows really strong genetic resistance.”

Similar uses of Genetic Engineering could also help to prevent swine flu and bird flu, both of which pose a risk of spreading to humans. Professor Sang is involved in work on the latter.

“We’re investigating using gene editing to edit a gene that was shown by colleagues at Imperial College London to be involved in bird flu virus infection. This is an exemplar of the sorts of things we can do with gene editing technology.”

Agri-TechE director Dr Belinda Clarke commented: “The use of New Genomic Technologies is currently restricted by legislation that predates the sequencing of the human genome and does not reflect the increasing diversity in the technology. Making legislation fit for purpose could bring many benefits.”

Another of the speakers at the event will be Professor of Livestock Informatics and team leader for Animal Breeding and Genomics at Scotland’s Rural College, Mike Coffey, who will be discussing how breeding for particular traits can reduce the environmental impacts of cattle.

Find out more about the virtual Agri-TechE event at agri-tech-e.co.uk