Home > Medical > Genetics > News 17 September 2013 Cold sores linked to a gene mutation Scientists have finally discovered why some people are prone to cold sores while others are not. 0 Shutterstock Related Cold sores Check Assess your diabetes risk » Quiz Am I at risk for COPD? » Ask CyberDoc » 10 ways to boost your metabolism World's Most Famous TB Patients Why some people are troubled by cold sores while others are not has finally been explained by scientists.Cold sores affect around one in five people but, until now, no one has been sure why some are more prone to the virus that causes them.Researchers at the University of Edinburgh have found that people affected by cold sores have a mutation in a gene, which means their immune system is not able to prevent them from developing. Cold sores are caused by a strain of the herpes simplex virus herpes simplex virus type 1 (HSV-1). Between 80 and 90% of people are infected with the virus, but only about a quarter of them get frequent cold sores.Scientists analysed thousands of genes to identify which ones expressed the proteins needed by the body's immune system to prevent the virus from becoming active and – as a result – cold sores from developing.Inadequate immune responseThey then looked at blood samples from people with cold sores and found that one of the genes previously identified – IL28b – was mutated. This genetic mutation means that the body is not able to mount an adequate immune response to the virus, which results in cold sores.The gene identified is also linked to treatment responses for hepatitis C patients. If this gene is mutated, patients are less likely to respond as well to treatment. The link is further evidence that a single genetic mutation can be linked to different viruses.The study, published in the journal Plos Pathogens, was funded by the Medical Research Council, the Biotechnology and Biological Sciences Research Council, the Wellcome Trust and the European Union.Professor Juergen Haas, of the University of Edinburgh's Division of Pathway Medicine, said: "Most people carry the cold sore strain of the herpes simplex virus, but until now we never knew why only some of them develop cold sores. "Knowing that susceptibility to the virus involved relates to people's genes reinforces the need to research, not only the evolution of viruses themselves, but also the susceptibility of hosts to infection." (Picture: cold sore from Shutterstock) EurekAlert More in Medical How your genes determine who you're attracted to More: GeneticsNews advertisement Get a quote Momentum - save up to 35% on healthcare advertisement Read Health24’s Comments Policy Comment on this story 0 comments Comments have been closed for this article. Logout Comment 0 characters remaining Share on Facebook Loading comments... Other news Fitness Dis-Chem pulls fitness supplement Jack3d from shelves Medical Aids is the leading killer of African teens Medical Physical activity may stave off cancer death Medical South African returns from the US for life-saving surgery Medical Paralysed man walks again – with electric connections Medical Adolescent deaths from AIDS tripled since 2000 From our sponsors How will we feed 9 billion people? Try the Meat Free Movember Challenge Fit starts now with MRP Sport Get Race Ready with REHIDRAT® Live healthier Toilet matters » 45 toilets in the world Poop in weird places Toilet paper debate The funniest bathroom signs ever These signs have taken toilet humour to the next level. Too Tired? » 20 signs of burnout Staying active reduces stress 10 ways to have a healthier work day Why you're exhausted Lost your mojo? Here are 5 surprising energy drainers, plus the easy fixes that will help put the pep back in your step!