Fibromyalgia sufferers may share a genetic link to a disease that has been dubbed a deadly mixture of dementia, Parkinson’s and motor neurone disease.
A major study has found an association between the long-term condition, which causes severe brain fog, fatigue and pain across the body, and Huntington’s disease.
Around 7,000 people in the UK are living with Huntington’s – a devastating and deadly inherited disorder that destroys nerve cells in the brain, robbing patients of their ability to move, think and control their behaviour.
Meanwhile, charities estimate that up to three million adults in the UK may have fibromyalgia, whose famous victims include Lady Gaga and Morgan Freeman, with thousands more undiagnosed.
A team of global researchers discovered the surprising link after analysing genetic data from more than 2.5 million adults, including around 55,000 with fibromyalgia.
They identified 26 genetic changes linked to fibromyalgia, many of which were found in brain and nervous system function.
The strongest signal, however, was found within the huntingtin (HTT) gene – the same gene that causes Huntington’s disease when faulty.
Authors of the study – published in Nature Medicine – say their findings change ‘how we think about fibromyalgia at a fundamental level’.
A study has found an association between fibromyalgia, which causes severe brain fog, fatigue and pain across the body, and Huntington’s disease
Scientists first discovered that the HTT gene is behind the incurable disease around 30 years ago, and have studied it intensely to gain a greater understanding.
Researchers of the new study say the findings may also overturn long-held beliefs about fibromyalgia, including the idea that it is purely psychological.
Michael Wainberg, an investigator at the Lunenfeld-Tanenbaum Research Institute and the University of Toronto and co-senior author on the paper, said: ‘This work changes how we think about fibromyalgia at a fundamental level.
‘For decades, patients have been dismissed or told their pain is simply psychological. Our findings confirm the condition has a clear biological basis.’
The researchers also said their findings suggest that fibromyalgia may be a disorder of the nervous system, rather than an autoimmune disease.
A 2021 study by King’s College London, which suggested many symptoms of fibromyalgia are caused by proteins that make pain-sensing nerves more active.
At the time, they said: ‘The results show that fibromyalgia is a disease of the immune system, rather than the currently held view that it originates in the brain.’
Fibromyalgia most commonly affects middle-aged women and is most often diagnosed after the age of 25.
Charities estimate that anywhere between 1.8million to 2.9 million people have the cruel illness.
And experts – separate to the studies – say the true number of those living with fibromyalgia may be even higher as it can often be hard to diagnose.
The NHS says symptoms can ‘vary from person to person’ but the most common one is widespread pain.
Around 7,000 people in the UK are living with Huntington’s – a devastating inherited disorder that destroys nerve cells in the brain
It can also cause its victims to be extremely sensitive to pain and bright lights, as well as triggering stiffness.
One of the most commonly reported symptoms, however, is so-called ‘fibro fog’ – where people have trouble remembering, concentrating and even speaking.
The new research also found strong links between fibromyalgia and other conditions like back pain, irritable bowel syndrome and post-traumatic stress disorder.
The researchers believe these conditions may share problems in the nervous system, which could explain why they often occur together.
Frances Williams, a rheumatologist at TwinsUK, King’s College London and co-author on the study, said: ‘We know that chronic pain syndromes cluster together in individuals and families and are genetically similar.
‘Targeting the shared mechanisms underlying them could potentially benefit a whole cluster of disorders.’
Despite the genetic links, the researchers stressed that genes alone are unlikely to explain why someone develops fibromyalgia.
Instead, they believe other triggers, such as a painful condition like arthritis, may be needed before the illness develops.
Nasa Sinnott-Armstrong at Fred Hutch Cancer Center and University of Washington in Seattle, said: ‘Understanding how genes, environmental exposures, and life events jointly contribute to risk of fibromyalgia syndrome is critical.
‘Further research into triggers of fibromyalgia and corresponding changes to neural tissues will help understand what drives fibromyalgia and how to treat it.’
Furthermore, the team also found no genetic differences between men and women, despite fibromyalgia being diagnosed around three times more often in women.
