The world’s largest genetic study into chronic fatigue syndrome is to be launched in the UK after receiving £3.2m of funding from the Medical Research Council and National Institute for Health Research. The research aims to shine a light on the debilitating long-term condition, about which little is known, by collecting DNA samples from 20,000 people who have CFS, also known as myalgic encephalomyelitis (ME). CFS is believed to affect about 250,000 people in the UK and has been estimated to cost the economy billions of pounds each year. Individuals experience exhaustion that is not helped by rest, with one in four so severely affected they are unable to leave the house and, frequently, unable to leave their bed. Other symptoms include, pain, mental fogginess, light and noise sensitivities, as well as trouble with memory and sleep. No effective treatment exists. The DecodeME study is being led by a partnership of scientists and patients including Andy Devereux-Cooke. He said: “As someone living with ME/CFS, I’m well aware that the patient community has waited a long time for a study such as this one that has such a strong, genuine element of patient involvement. All of us involved with this research project hope that it can start to address the totally unwarranted stigma and lack of understanding that so many patients with ME/CFS face on a daily basis.” The hope is the study will aid development of diagnostic tests and targeted treatments by pinpointing tiny differences in a person’s DNA that may affect their risk of developing CFS and reveal the underlying causes of the condition. The samples will be compared with a similar number of non-CFS matched controls, which could be drawn from the UK Biobank. Principal investigator Prof Chris Ponting from the human genetics unit at the University of Edinburgh said: “Our focus will be on DNA differences that increase a person’s risk of becoming ill with ME/CFS. We chose to study DNA because significant differences between people with, and without, ME/CFS must reflect a biological cause of the illness. It is our hope that this study will transform ME/CFS research by injecting much-needed robust evidence into the field.” People with CFS who are aged 16 and over can volunteer to take part from home by signing up on the study website. When it begins, they will be mailed a collection kit and asked to send back a saliva sample, which will be compared with those from healthy controls. Genome-wide association studies have previously helped uncover the biological roots of many other complex diseases, including type 2 diabetes and Alzheimer’s disease.