Scientists at the Roslin Institute in Edinburgh have created gene-edited pigs that are resistant to classical swine fever (CSF), a highly contagious and often fatal viral disease. The breakthrough was demonstrated in trials at the Animal and Plant Health Agency (APHA), where gene-edited pigs remained healthy after exposure to the virus, while control animals developed symptoms within a week.
Classical swine fever, also known as hog cholera, causes fever, skin lesions, convulsions, diarrhoea and often death within 15 days. Although eradicated in the UK in 1966, periodic outbreaks have led to the culling of 75,000 pigs. The disease remains endemic in countries such as China, Russia and Brazil, where it is controlled through costly vaccination programmes and trade restrictions.
The study targeted a gene responsible for producing the protein DNAJC14, which plays a critical role in pestivirus replication. By altering a few letters of the DNA code, the scientists blocked viral replication. Several generations of gene-edited pigs were monitored, showing no adverse effects on health or fertility.
Dr Christine Tait-Burkard of the Roslin Institute said: 'This virus has a severe effect on animal welfare and productivity.' The team is now investigating whether the same gene edit can confer resistance to related pestiviruses that infect cattle and sheep in the UK.
The advance comes as the UK's Precision Breeding Act paves the way for gene-edited livestock. Dr Simon Lillico, a co-author, stated: 'In my mind there is a moral imperative that if we can make animals that are disease resistant then we probably should do.' The findings are published in the journal Trends in Biotechnology.
