People from South Asian, African and European backgrounds share many of the same genetic risk factors for MS, a UK study has found.
MS affects around 150,000 people in the UK and more than 2m worldwide, yet most genetic research so far has focused on people of white European ancestry.
The new study, one of the most diverse UK genetic analyses of MS, examined data from more than 3,000 people with the condition and over 27,000 without it.
Participants came from the ADAMS Project, which recruits people with MS from diverse backgrounds, and from the UK Biobank.
Ruth Dobson, professor of clinical neurology at Queen Mary University of London and lead author of the study, said: “MS genetics has, until now, been overwhelmingly based on people of European ancestry.
“This study shows that while many of the biological pathways driving MS are shared, leaving large parts of the global population out of research limits our understanding of the disease.
“Better representation is not only a fairness issue, it leads to better science.”
Researchers found that genetic variants in the major histocompatibility complex region, a part of the immune system long linked to MS risk, were strongly associated with MS in people of South Asian and African ancestry, as well as in people of European ancestry.
There was also evidence that some genetic patterns differed between groups.
The team identified a variant that may lower the risk of MS and is relatively common in people of South Asian ancestry but rare in those of European descent.
Because this variant is uncommon in Europeans, it would probably be missed in studies that only include European populations.
The study also found that most genetic variants previously identified in European populations appear to be present in people of South Asian and African ancestry. #
While the strength of these effects varied, the overall pattern suggests MS is driven by shared immune and biological mechanisms across populations, rather than being a fundamentally different disease in different ancestry groups.
Previous research has shown stark racial disparities in MS outcomes, with people from Black ethnic backgrounds often experiencing more severe disability and worse disease trajectories than their white counterparts.
Differences in genetics alone do not explain these inequalities, but the historic lack of representation of South Asian and Black populations in genetic research means MS may be under-recognised, diagnosed later or assessed less accurately in these groups.
It also means there is less certainty that genetic risk tools, and potentially treatments developed using European-focused data, perform equally well for everyone.
Benjamin Jacobs, clinical lecturer in neurology at Queen Mary University of London and co-author of the study, said: “This work demonstrates why diversity matters in genetics.
“When studies only include one ancestral group, they miss important insights.
“By broadening participation, we can sharpen our understanding of MS, find risk factors that would otherwise stay hidden and build prediction tools that work for everyone.”
Caitlin Astbury, senior research communications manager at the MS Society, added: “Over 150,000 people live with MS in the UK, and the condition can affect all communities, ages, ethnic backgrounds and genders.
“MS is likely to be caused by a combination of factors, including lifestyle, environment, and genetics.
“But almost everything we know about genes and MS comes from studies looking at people of white European descent.
“Making sure we include people from diverse backgrounds in research is key and the ADAMS study is leading the way.
“Research like this is vital to ensure that progress in MS treatments, diagnosis, and risk prediction benefits everyone.”
The authors noted that this disparity reflects the European-dominant data used to develop these tools and highlights why broader representation matters for equitable predictive genetics.
