For years, people with crushing fatigue have fought for answers, bouncing between clinics and labels that never quite fit well.
A team from the University of East Anglia and Oxford Biodynamics says a new blood test can identify myalgic encephalomyelitis/chronic fatigue syndrome with striking accuracy, giving a concrete signal where patients once faced only doubt and delay.
What the new test measures
The test uses EpiSwitch 3D Genomics, a technology that tracks how DNA folds inside cells. These three-dimensional patterns, known as chromatin conformations, act like molecular signposts. In early data, patients meeting clinical criteria for ME/CFS showed a distinctive genomic folding signature that separated them from healthy controls. That signature can be picked up from a standard blood sample.
Early results report 92% sensitivity and 98% specificity for identifying a genomic folding pattern linked to ME/CFS.
Because the readout is binary rather than subjective, the approach could complement clinical assessments and cut through uncertainty. The method does not rely on a single gene or protein. It maps a panel of structural genomic markers that together point to disease biology.
Why this matters for patients and the NHS
Diagnosis for ME/CFS currently rests on careful history-taking, symptom patterns, and exclusion of other conditions. That process can stretch over months or years, during which many people struggle to access support at work, school, or through benefits systems. A reliable laboratory signal could change that trajectory.
- Faster answers: earlier recognition can guide pacing strategies and stop harmful overexertion.
- Fewer dead-ends: objective results may reduce referrals that circle back without clarity.
- Better trials: a stable biomarker helps researchers build cleaner studies and compare treatments.
- Policy impact: measurable disease signals often unlock commissioning and service planning.
About 400,000 people in the UK live with ME/CFS. Many spend years without a firm diagnosis or effective support.
What the numbers really mean
Sensitivity of 92% suggests the test correctly flags most people who have the condition. Specificity of 98% indicates it rarely labels someone without the condition as positive. Those figures look strong, yet they come from an initial dataset. Performance can shift when a test moves into routine clinics with broader, more complex patient groups.
Doctors will still need to interpret results in context. No test lives in isolation. A positive signal would add weight to a clinical picture that already points to ME/CFS. A negative result might prompt a fresh look for other causes of fatigue, pain, or cognitive difficulties.
How the pathway could change
| Today | With a validated blood test |
|---|---|
| Diagnosis by symptoms after exclusion of lookalike conditions | Symptom assessment plus a blood test that supports or challenges the working diagnosis |
| Months to years to reach a decision | Potential for weeks, depending on lab availability |
| High risk of mislabelling or dismissal | Objective signal may reduce doubt and delay |
| Trial recruitment hampered by heterogeneous cohorts | Biomarker-enriched cohorts for more decisive trials |
| Limited tools to track biological change | Scope to monitor a molecular signature alongside symptoms |
The science in plain terms
Genes sit on DNA strands that coil and loop in three-dimensional space. Those loops bring distant sections together, switching networks of genes on or off. Illness can reshape these loops. The EpiSwitch platform reads that architecture across select regions of the genome and looks for a pattern that correlates with disease. It’s not sequencing mutations, and it’s not measuring autoantibodies. It’s reading structure.
That structure can reflect immune dysregulation, metabolic strain, or cellular stress. Researchers argue the pattern they see in ME/CFS matches biological changes suspected for years by clinicians and patients, lending weight to a disease model grounded in measurable dysfunction.
Questions that need answers next
- Can the signal distinguish ME/CFS from long Covid, fibromyalgia, depression, sleep apnoea, thyroid disease, or anaemia?
- Does the test perform equally well across age groups, sexes, ethnic backgrounds, and severities, including housebound patients?
- How stable is the signature over time, during flares, or after infections and vaccinations?
- What pre-analytical steps matter most: fasting, time of day, shipping temperature, or storage?
- Will NHS laboratories be able to run the assay at scale, and at what cost per sample?
Independent validation across larger, mixed patient groups will decide whether this moves from promise to practice.
Where validation and rollout could lead
If independent centres reproduce the reported accuracy, regulators could evaluate the assay for clinical use. Health systems then look at cost-effectiveness: does the test shorten time to diagnosis, reduce repeat appointments, and improve quality of life? Commissioners will ask whether results change management in ways that save money and improve outcomes. Research funders may use the biomarker to stratify treatment trials, a step that often accelerates progress.
Clinics could add the assay early in the pathway. A positive signal might fast-track a care plan aligned with NICE guidance: energy management, symptom control, and adjustments at work or school. A negative signal would push clinicians to reassess for other conditions with overlapping symptoms.
What this means for people living with chronic fatigue
People often wait years to be believed. A lab readout does not replace lived experience, yet it can shift attitudes across workplaces, classrooms, and consulting rooms. Families gain a clearer framework for pacing daily tasks. Employers have firmer grounds for adjustments. Teachers can plan predictable rest breaks and reduced cognitive load for pupils with persistent symptoms.
For those looking to prepare for a future test request, keep a concise symptom diary: note activity, post-exertional malaise, sleep quality, dizziness, pain, and cognitive fog, alongside infections or stressors. Bring past blood results and medication lists to appointments. Ask whether a structured functional assessment, such as a six-minute walk with symptom follow-up, could document post-exertional effects without pushing beyond safe limits.
Key terms to know before you speak to your GP
- Post-exertional malaise: a delayed worsening of symptoms after even minor activity.
- Orthostatic intolerance: symptoms that appear or worsen when standing, linked to circulation changes.
- Unrefreshing sleep: poor restoration despite long hours in bed.
- Cognitive dysfunction: difficulty processing information, memory lapses, slowed thinking.
The wider research picture
Biomarkers rarely arrive alone. As labs refine technology like 3D genomics, parallel work in metabolomics, immune profiling, and autonomic testing continues. Convergence across methods builds confidence. If multiple tools point to the same biology, treatment targets become clearer. That approach has transformed fields from oncology to rheumatology. ME/CFS research now has a candidate marker that could anchor similar progress.
For carers and patients, the hope is practical: shorter waits, fewer fruitless referrals, and trials that finally test targeted therapies. For clinicians, a reliable blood test could strengthen confidence when discussing diagnosis and prognosis. For researchers, a reproducible signature offers a shared language to design the next wave of studies.
