Scientists develop a high accuracy blood test to diagnose Chronic Fatigue Syndrome

Scientists at the University of East Anglia and Oxford Biodynamics have developed a high accuracy blood test to diagnose Chronic Fatigue Syndrome, also known as Myalgic Encephalomyelitis (ME/CFS).

The debilitating long-term illness affects millions worldwide - including over 400,000 sufferers in the UK - but is poorly understood and has long lacked reliable diagnostic tools.

With 96 per cent accuracy, the test offers new hope for those living with the condition - which is often misunderstood and misdiagnosed.

And it is hoped that the breakthrough could pave the way for a similar blood test to diagnose long Covid.

Lead researcher Prof. Dmitry Pshezhetskiy, from UEA's Norwich Medical School, said: "ME/CFS is a serious and often disabling illness characterised by extreme fatigue that is not relieved by rest.

"We know that some patients report being ignored or even told that their illness is 'all in their head'.

"With no definitive tests, many patients have gone undiagnosed or misdiagnosed for years.

"We wanted to see if we could develop a blood test to diagnose the condition – and we did!

"Our discovery offers the potential for a simple, accurate blood test to help confirm a diagnosis, which could lead to earlier support and more effective management."

"Post-Covid syndrome, commonly referred to as long Covid, is one example of ME/CFS, where a similar cluster of symptoms is triggered by the Covid-19 virus, rather than by other known causes such as glandular fever. We therefore hope that our research will also help pave the way for a similar test to accurately diagnose long Covid."

How the discovery was made

The team used advanced EpiSwitch® 3D Genomics technology from Oxford BioDynamics (AIM:OBD) to see how DNA is folded in blood samples from 47 patients with severe ME/CFS and 61 healthy controls.

Each of our cells contains about two metres of DNA, packed tightly and folded in 3D. These folds aren't random - millions of them are deliberate, forming a hidden code that helps turn genes on or off to keep us healthy.

Chronic Fatigue Syndrome is not a genetic disease you're born with. That's why using EpiSwitch 'epigenetic' markers - which can change during a person's life, unlike fixed genetic code - was key to reaching this high level of accuracy.

The EpiSwitch platform behind this test, together with OBD's vast 3D Genomic knowledgebase, has already been proven to deliver practical, rapid blood diagnostics accessible at scale.

With this breakthrough, we are proud to enable a first-in-class test that can address an unmet need for a quick and reliable diagnostic for a complex, challenging-to-identify illness."

Alexandre Akoulitchev, OBD Chief Scientific Officer

This approach using EpiSwitch has previously shown success in identifying disease-specific blood markers in highly complex inflammatory and neurological conditions such as fast ALS (amyotrophic lateral sclerosis), rheumatoid arthritis, and certain cancers. This includes the EpiSwitch PSE test, which is a blood test with world-leading accuracy for prostate cancer already used in the UK and US.

The team discovered a unique pattern that appears consistently in people with ME/CFS that is not seen in healthy people.

Using a different approach, this work looked beyond the linear DNA sequence investigated by a previously published DecodeME study, the largest genetic investigation of ME/CFS to date.

By examining 3D genomic folds, UEA and Oxford BioDynamics revealed hundreds of additional changes, including five of the eight sites identified by DecodeME, which can now provide a deeper understanding of the disease.

The analysis showed remarkable accuracy – with 92 per cent sensitivity in identifying ME/CFS, which indicates how well the test identifies those who have the disease (a show of true positives) and 98 per cent specificity, which indicates how well it identifies those who do not have the disease.

The researchers also found signs of immune system and inflammation pathways involved in the disease, which may help guide future treatments and identify patients more likely to respond to specific therapies.

A vital tool for diagnosis and treatment

"This is a significant step forward," said UEA's Prof Pshezhetskiy. "For the first time, we have a simple blood test that can reliably identify ME/CFS - potentially transforming how we diagnose and manage this complex disease."

"Additionally, understanding the biological pathways involved in ME/CFS opens the door to developing targeted treatments and identifying which patients might benefit most from specific therapies.

"We hope that the Episwitch^® CFS test could become a vital tool in clinical settings, paving the way for more personalized and effective care."

This research was led by UEA and Oxford BioDynamics in collaboration with The London School of Hygiene & Tropical Medicine and Royal Cornwall Hospitals NHS Trust.