At McGill University's Neuro Institute in Montreal, researchers have discovered a small group of altered blood proteins that could reveal who will develop multiple sclerosis years—sometimes more than a decade—before the disease strikes. The finding, published in May 2026 in the Annals of Neurology, offers a rare window of opportunity: the chance to intervene before the neurological damage that defines MS takes hold.
Multiple sclerosis is one of those cruel diseases where timing is everything. The damage wrought by MS on the brain and nervous system is notoriously difficult to reverse once it occurs, yet early intervention can prevent many of the worst symptoms from ever developing. The problem, until now, has been knowing who to treat. Most people only receive an MS diagnosis after the disease is already underway, after that critical window for prevention has closed.
Dr. Adil Harroud, a neurologist and researcher at the Neuro, led a team that screened more than 2,500 blood proteins to identify which ones might signal future MS risk. Using a statistical technique called Mendelian Randomization, they identified 39 proteins linked to MS, most involved in immune cell signaling. But the real breakthrough came when they turned to the UK Biobank, a vast health database that collected blood samples from half a million volunteers between 2006 and 2010 and tracked their health for years afterward.
Among those half-million volunteers, 124 people eventually developed MS. The researchers pulled blood samples from these individuals collected an average of six years before their diagnosis—and in some cases, more than a decade earlier. When they analyzed those archived samples, eight proteins stood out: they were already altered in people who would go on to develop the disease.
One protein, DKKL1, proved particularly striking. People with higher levels of DKKL1 not only had lower risk of developing MS altogether, but if they did develop it, their disease followed a milder course. "This is a candidate marker for both risk and prognosis," the research team noted—meaning a single protein might tell doctors not just who will get sick, but how severely.
The parallel to cholesterol screening is instructive. Just as blood cholesterol levels can flag heart disease risk years before a heart attack occurs, giving doctors time to intervene, these eight proteins could serve as an early-warning system for MS. The logic is straightforward, yet its implications are profound.
Dr. Harroud emphasizes what's now at stake: "In MS, we now know that intervening early can delay or even prevent symptoms altogether. 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 is done."
The research team is now planning to validate their findings in larger populations and to test whether these markers, combined with other clinical tools, can be developed into practical screening tests. For the millions living with MS—and millions more at genetic risk—that validation work represents the next critical step toward turning prevention from hope into routine practice.