The body leaves traces of MS years before the mind feels it
For generations, multiple sclerosis has announced itself only after the damage is already done — a diagnosis arriving late to a crisis long underway. Researchers at McGill University's Montreal Neurological Institute-Hospital have now identified eight proteins in the blood that shift measurably years before any symptom appears, offering medicine a rare gift: time. The discovery, validated against pre-diagnostic samples from the UK Biobank, suggests that the body quietly signals its vulnerability long before the nervous system begins to fail — and that learning to read those signals could change the course of the disease entirely.
- Multiple sclerosis causes irreversible neurological damage that often begins years before a patient receives any diagnosis, leaving doctors with little room to intervene.
- A McGill University team sifted through more than 2,500 blood proteins using Mendelian randomization, narrowing the field to eight biomarkers that show measurable changes six or more years before MS onset.
- Validation against 124 pre-diagnostic cases in the UK Biobank confirmed the signal is real — one protein, DKKL1, may even indicate how severe the disease will become, not just whether it will arrive.
- The research, published in Annals of Neurology in May 2026, has not yet reached clinical use, but it maps a credible path toward presymptomatic screening for at-risk populations.
- The next challenge is scale — larger validation cohorts and practical screening frameworks are needed before these markers can guide real treatment decisions.
Multiple sclerosis damages the nervous system in ways that are often permanent, and by the time most patients are diagnosed, the disease has already been at work for years. Doctors have long sought a way to see it coming. A team at McGill University's Montreal Neurological Institute-Hospital may have found one.
The researchers began with more than 2,500 blood proteins, using a statistical method called Mendelian randomization to identify which ones might be linked to MS risk. From that search, 39 proteins emerged as candidates — but candidates needed to be tested against real human data. The team turned to the UK Biobank, a repository of blood samples and health records from roughly 500,000 volunteers tracked since the mid-2000s, and located 124 individuals who had later developed MS.
Looking back at blood drawn an average of six years before those diagnoses, the researchers found eight proteins that had already shifted — measurable changes with no accompanying symptoms. One protein, DKKL1, appeared not only to signal risk but to influence how severe the disease became, suggesting it could serve as both an early warning and a prognostic tool.
Published in Annals of Neurology in May 2026, the findings point toward a future in which blood tests identify MS risk years before the nervous system shows any sign of strain. Dr. Adil Harroud noted that early intervention can now delay or prevent symptoms — the obstacle has always been knowing who to treat. These markers offer a potential answer.
The work is not yet ready for clinical use. Larger validation studies are needed, and researchers must determine whether these proteins, alone or alongside other tools, can anchor a practical screening strategy. But the underlying principle is striking: the body encodes the coming of MS in its blood long before the disease makes itself known.
Multiple sclerosis damages the nervous system in ways that are often permanent. By the time most patients receive a diagnosis, the disease has already begun its work—sometimes for years. Doctors have long wished for a way to spot the illness coming, to intervene before that damage takes hold. A team at McGill University's Montreal Neurological Institute-Hospital has found something that might make that possible: certain proteins in the blood shift measurably years before a person ever shows symptoms of MS.
The researchers began by examining more than 2,500 blood proteins, using a statistical method called Mendelian randomization to sort through which ones might be connected to MS risk. They identified 39 proteins involved in immune cell signaling pathways that appeared to matter. But identifying candidates in theory is different from finding them in real people. So the team turned to the UK Biobank, a vast collection of blood samples and health records from roughly 500,000 volunteers whose samples were drawn between 2006 and 2010 and whose health has been tracked ever since.
They located 124 people in that database who had later developed MS. By looking back at blood samples taken an average of six years before those people were diagnosed, the researchers could see what their protein profiles looked like in the presymptomatic window. Eight proteins showed measurable changes in those early samples—changes that preceded any clinical sign of illness. One protein in particular, called DKKL1, appeared to protect against MS or to soften its course in people who did develop it, suggesting it might serve both as a risk marker and as a predictor of disease severity.
The findings, published in Annals of Neurology in May 2026, point toward a practical possibility: blood tests that could identify people at risk years before symptoms appear. Dr. Adil Harroud, a neurologist and researcher at the Montreal institute, noted that early intervention in MS can now delay or even prevent symptoms entirely. The missing piece has always been knowing who to treat. These protein markers offer a potential answer—a way to act before the damage begins.
The work is not yet ready for clinical use. The researchers acknowledge that the next phase requires validation in larger populations and testing whether these markers, alone or combined with other tools, could form the basis of a practical screening approach. But the principle is clear: the body leaves traces of MS years before the mind or body feels it. Learning to read those traces could transform how the disease is managed.
Notable Quotes
In multiple sclerosis, we now know that early intervention can delay or even prevent symptoms entirely. What we lack is a way to identify the right people in time. These blood markers point toward a way to do that and to act before damage occurs.— Dr. Adil Harroud, Montreal Neurological Institute-Hospital, McGill University
The Hearth Conversation Another angle on the story
Why does it matter that these proteins change six years before diagnosis rather than, say, one year before?
Because six years is a window. It's time to intervene before the immune system has scarred the nervous system. Once that scarring happens, it's often permanent. Early treatment now can prevent symptoms entirely—but only if you catch it early enough.
So this isn't just about diagnosis. It's about prevention.
Exactly. Right now, doctors treat MS after it announces itself. These markers could let them treat it while it's still silent, before the person even knows they're sick.
What's DKKL1 doing differently from the other seven proteins?
It seems to be protective. People with higher levels of it are less likely to develop MS, and if they do, they tend to have milder disease. That makes it useful both for identifying risk and for predicting how severe the illness might be.
How confident are they that this will actually work in practice?
They're not claiming it will yet. They've found the signal in one dataset. The next step is testing it in other populations to make sure the pattern holds. That's the honest part of the work—they know this is promising but not proven.
What happens to someone who tests positive for these markers but never develops MS?
That's the real question. Some people might carry the markers and never get sick. That's why validation in larger groups matters—you need to know how many false alarms you'll get before you start screening millions of people.