Initial findings have uncovered eight areas of genetic code in people with ME/CFS (myalgic encephalomyelitis/chronic fatigue syndrome) that are markedly different to the DNA of people without the condition.
Results from the landmark DecodeME study, the largest of its kind in the world, provide a major step forward in understanding the biological roots of ME/CFS and suggest that both the immune system and nervous system are involved in its development, experts say.
The findings – first reported in a pre-print publication, or unpublished study – represent a milestone in ME/CFS research and can now help guide the search for effective treatments, placing this long-neglected disease on equal terms with other debilitating conditions, researchers say.
Debilitating illness
ME/CFS’ key feature, known as Post-Exertional Malaise (PEM), is a disproportionate worsening of symptoms following even minor physical or mental activity. Other symptoms include pain, brain fog and extreme energy limitations that do not improve with rest.
Very little has been known about the causes of ME/CFS and there is currently no diagnostic test or cure. It is believed to affect around 67 million people worldwide.
Genetic discovery
For the new study researchers analysed 15,579 DNA samples from the 27,000 people with ME/CFS participating in DecodeME – the world's largest data set of people with the disease.
They found eight regions of DNA where genetic differences were significantly more common in people with ME/CFS than in the general population.
These differences – also known as genetic signals – involve genes linked to the immune and nervous systems.
Biological insight
At least two of the genetic signals relate to how the body responds to infection, which aligns with longstanding patient reports that the onset of symptoms often followed an infectious illness.
Another has previously been identified in those experiencing chronic pain, a symptom commonly described by those living with ME/CFS.
As a person’s DNA does not change over time, experts say the genetic signals identified would not have developed because of ME/CFS and are therefore likely to reflect the causes of the disease.
Populations used in this initial study were limited to those from European ancestries. DecodeME research studying DNA data from all ancestries is ongoing.
Global call
Researchers say the findings are not yet ready to inform treatment or diagnosis but offer vital clues to the disease’s origins and could guide future drug development.
The DecodeME team is now calling on researchers from around the world to access its rich dataset and help drive forward targeted studies into ME/CFS, particularly those linked to the eight newly identified genetic signals.