Blood Proteins May Flag Multiple Sclerosis Risk Years Before Symptoms Appear

A blood test capable of detecting multiple sclerosis before the disease takes hold could move closer to reality following a new study that identified proteins associated with MS risk years—and in some cases more than a decade—ahead of diagnosis.

The findings, published in Annals of Neurology, come from a team led by Adil Harroud, a neurologist and researcher at The Neuro (Montreal Neurological Institute-Hospital) of McGill University.

The challenge driving the work is a familiar one in neurological disease: by the time MS is diagnosed, significant brain damage has often already occurred, and that damage is difficult or impossible to repair. Earlier detection could change that calculus. “In MS, we now know that intervening early can delay or even prevent symptoms altogether,” said Dr. Harroud. “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.”

To find those markers, the team screened more than 2,500 blood proteins using Mendelian Randomization, identifying 39 linked to MS risk. Most fell within the signaling pathways immune cells use to communicate. The researchers then turned to UK Biobank, which collected blood samples from half a million volunteers between 2006 and 2010 and tracked their health since. Among those participants, 124 went on to develop MS, giving the team the ability to examine blood samples taken an average of six years before diagnosis. 

Of the 39 candidate proteins, eight were already altered in people who would later be diagnosed with MS. One protein, DKKL1, stood out: it was associated with both a lower risk of developing the disease and a milder course in those who did develop it, making it a potential marker for both risk and prognosis. The approach draws a parallel to cholesterol screening for heart disease, where elevated blood levels can signal risk well before a cardiac event. 

The team plans to validate these findings in larger patient groups and explore whether the markers, used alongside other diagnostic tools, could form the basis of a clinical screening test.