Scientists at the University of East Anglia have discovered genetic changes in chronic fatigue syndrome patients that prove the illness has a physical cause.
The research team identified an epigenetic switch affecting energy production that is shared across five major illnesses, raising hopes for a single therapy that could treat chronic fatigue in around 5.7 million Britons.
Alongside chronic fatigue syndrome, which affects more than 400,000 people in the UK, the study found the same genetic mechanism in long Covid, multiple sclerosis, rheumatoid arthritis, and post-traumatic stress disorder. Long Covid alone affects between 1.8 million and 2 million people across the country.
The findings, published earlier this month in the Journal of Translational Medicine, suggest that environmental factors such as stress and diet alter gene behaviour to disrupt energy production, metabolism regulation, infection response, and stress response.
Research lead Professor Dmitry Pshezhetskiy, a specialist in treating myalgic encephalomyelitis and chronic fatigue syndrome, told Good Health that the discovery offers biological proof of the illness.
"The thing that links all these conditions is that patients frequently report remarkably similar symptoms: overwhelming fatigue, brain fog, poor concentration, disturbed sleep and a dramatic reduction in everyday functioning," Professor Pshezhetskiy said.
He added: "One of the most significant aspects of this discovery is that it provides objective, blood-based biological proof of disease."
Epigenetic switches and energy disruption
Myalgic encephalomyelitis, commonly known as ME or chronic fatigue syndrome (CFS), is a condition characterised by debilitating fatigue, brain fog, sleeping problems, dizziness, and pain. Mainstream medicine acknowledged the existence of the illness more than 30 years ago, but debate over its legitimacy has persisted since the 1980s, when it was dubbed "yuppie flu" because it appeared to affect mainly young professionals.
Scepticism surrounding the condition has stemmed partly from the variety of non-specific symptoms reported by sufferers. In 2021, the National Institute for Health and Care Excellence updated its guidelines, doing a U-turn on previous medical advice that encouraged patients to exercise regardless of post-exertional symptoms.
The University of East Anglia study adds to a growing body of scientific evidence highlighting physical causes for the condition. Last year, an Australian study published in the journal Cell revealed that chronic fatigue syndrome was linked to simultaneous disruptions in how the body generates energy and regulates the immune system. Other research has suggested that chronic exhaustion occurs when an over-reactive immune system treats routine stress as an infection, causing exhausting flu-like symptoms.
Professor Pshezhetskiy expressed hope that the team's findings will lead to a blood test for rapid diagnosis and the development of targeted epigenetic drugs designed to reprogramme cell signalling to a healthy state. He told Good Health that such treatments could prevent patients from enduring years of misdiagnosis and medical gaslighting.
Patient experience of medical disbelief
For patients like Emma Slack, a 35-year-old mother of one from Newcastle, evidence of a distinct genetic cause offers long-awaited validation after years of experiencing medical skepticism and dismissiveness.
Emma became ill in 2008 at the age of 17 following a viral illness suspected to be glandular fever. Before contracting the illness, she was very active as a keen runner and dancer, but she never recovered her energy levels.
"I became unwell with a viral illness that was suspected to be glandular fever," she said. "I felt fluey with muscle aches and was so nauseous that I could not eat and I had fainting attacks."
Doctors initially attributed her symptoms to anxiety and sent her for counselling. Her counsellor claimed her physical suffering was caused by her inner child being stubborn and advised her to tell herself she was okay. When she was urged to push herself harder, her symptoms deteriorated significantly.
"They told me that the symptoms were just down to 'my inner child being stubborn, and that I needed to tell them that I was OK'," Emma recalled.
While studying for her degree, Emma suffered severe symptoms, eventually completing her PhD in epidemiology while working part-time and from home. In 2017, a specialist finally diagnosed her with chronic fatigue syndrome.
"It was a huge relief to have a diagnosis that finally made sense," she said. "However, this brought the realisation that there was nothing anyone in medicine could really do for me. There was no treatment offered, only advice on managing my condition by pacing myself."
Pregnancy and ongoing flare-ups
Medical dismissiveness persisted even after her diagnosis. When Emma became pregnant in 2022, her first obstetrician refused to engage with her condition or evaluate how it might impact her pregnancy, forcing her to seek out a different doctor who was willing to listen.
"During my pregnancy, my symptoms got worse: and they continued to worsen afterwards when I was breastfeeding," Emma said. Research indicates that pregnancy affects chronic fatigue syndrome patients unpredictably, with some women experiencing worsening symptoms, others improving, and some seeing no change.
Now working as a research engagement officer for the charity ME Research UK, Emma reported that her health has stabilised over the past four years. However, she still suffers severe flare-ups that leave her needing help to get upstairs or unable to answer simple questions.
"There are still times when I need help just to get up the stairs," she said. "Often a flare-up means I'm in bed for a day or two. My brain function goes and I can't even answer simple questions."
Expert caution over findings
Despite the findings, other medical experts have urged caution regarding the conclusions of the study. Dr Charles Shepherd, an honorary medical adviser to the UK charity the ME Association, stated that the organization considers the conclusions speculative and unproven, noting that more research is required.
"Another problem is that, having identified these as areas with underlying pathology, how do we fix them? How do we repair dysfunctional immune systems and improve cells' energy production? Science doesn't know at the moment," Dr Shepherd told Good Health.
He added: "Until we fully understand the mechanisms underlying CFS, we will just be tackling symptoms. But it is helpful that there is growing recognition that chronic fatigue syndromes are real."
Professor Carmine Pariante, a professor of biological psychiatry at King's College London, warned that the research does not identify novel mechanisms or concepts. However, he noted that the confirmatory evidence will be helpful for researchers in the field and for people living with these disorders.
