New Scientist
Scientists have found the first strong genetic evidence for chronic fatigue syndrome also called ME. A UK study of over 275,000 people revealed eight genetic regions linked to the illness tied to the brain and immune system. Experts say this could lead to better diagnosis and treatments.
Genetic signal seen in chronic fatigue
Author: Michael Marshall
GENETIC factors that could contribute to people’s risk of developing chronic fatigue syndrome (CFS), also known as myalgic encephalomyelitis (ME), have been identified.
“Our study provides the first robust evidence of genetic contributions to ME,” says Sonya Chowdhury at the charity Action for ME in the UK.
In the long run, the findings could contribute to the development of new diagnostic tools and treatments for ME/CFS, which has been recognised for decades and is marked chiefly by post-exertional malaise, a severe and debilitating response to even mild exertion.
Already, the results provide “validity and credibility” for people with the condition, says Chowdhury. “They’ve been to doctors and been disbelieved and told it’s not a real illness,” she says.
“This will be huge for the patient population,” says Andy Devereux-Cooke, co-founder of the Science for ME forum, who has had the condition for 45 years.
This provides validity for people with the condition, who have been told it’s not a real illness
The study, called DecodeME, compared DNA samples from just over 15,500 people with ME/CFS and nearly 260,000 without, all of whom were from the UK and of European ancestry.
“We have found eight genetic signals,” says Chris Ponting at the University of Edinburgh in the UK. The eight genome regions involved look significantly different in people with ME/CFS, indicating that genetic variants there contribute to the risk of developing it. The University of Edinburgh announced the findings in a press briefing, but they haven’t yet been published in a journal or on a preprint server.
Within these eight regions, the team identified 43 protein-coding genes, of which 29 looked especially promising. “When we dig down into these eight different genetic signals, we find genes that are related to both the immune system and the nervous system,” says Ponting. “Overall, the activities of the genes in these signals are enriched in the brain’s tissues. They are more likely to be active in the brain than elsewhere, pointing to a nervous system involvement.”
The researchers also identified an immune system-related gene called RABGAP1L as a probable contributor to ME/CFS risk. This fits with the testimony of most people with the condition, who say that an initial infection, often one that seemed mild, preceded the onset of their symptoms.
“My thought has always been that there is something different about the immune system in people with ME/CFS,” says Jackie Cliff at Brunel University of London.
The work didn’t find any differences in genetic risk between men and women, even though ME/CFS is much more common in women. However, the team hasn’t yet analysed the X and Y chromosomes.
The next step is to study in more detail the eight regions of the genome that have been highlighted, to try to figure out how the genetic alterations are translated into molecular and cellular processes in people with and without ME/CFS.
Credits: TCA, LLC.