Recent research has shed light on the genetic risk for multiple sclerosis (MS) and its origins, revealing intriguing insights into the disease’s prevalence in Northern Europe. The study, which utilized a large ancient genome dataset spanning the Mesolithic period to the Bronze Age, along with additional Medieval and post-Medieval genomes, identified a notable emergence of MS genetic risk among pastoralists from the Pontic steppe approximately 5,000 years ago. This genetic predisposition was subsequently introduced to Europe through the Yamnaya-related migration.

The findings also unveiled that the MS-associated immunogenetic variants experienced positive selection within the steppe population and later in Europe. This evolutionary trajectory was likely influenced by pathogenic challenges coinciding with changes in diet, lifestyle, and population density during the Neolithic period and Bronze Age. The study underscores the pivotal role of these historical periods in shaping modern immune responses and their impact on MS susceptibility in a changing environment.