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 Scientists question ethics of 'designer babies' More: GeneticsNews SPONSORED: Fedhealth What cover is right for you? advertisement Get a quote Fedhealth - What cover is right for you? Momentum - save up to 35% on healthcare advertisement Read Health24’s Comments Policy Comment on this story 0 comments Add your comment Thank you, your comment has been submitted. Logout Comment 0 characters remaining Share on Facebook Logout Comment 0 characters remaining Share on Facebook Loading comments... Other news Parenting Noakes' 'real food' may not be kid friendly Columnists Flying the flag for better healthcare in Africa Parenting Diet tips for pregnant moms – Part II Diet and nutrition Why mushrooms are good for you Medical Depression linked to many heart failure patients' death Medical Can asthma protect men from prostate cancer? From our sponsors Is your baby dehydrated? How to tell. Taking charge of your health Man, take care of your health! Live healthier 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! Kick the habit » Cancer doesn't make smokers to quit Non-smokers don't use e-cigs Hookah contains benzene How South Africans quit smoking We asked ex-smokers to share their secrets to successfully quitting smoking. Find out how they managed to kick the habit.