With its prevalence growing globally, multiple sclerosis (MS) is the most common disabling neurologic disease to affect young adults, especially women. Although the etiology and pathogenesis of the disease remains elusive, there has been a surge of research investigating risk factors for MS in recent years. MS genetics studies over the past decade have identified hundreds of genetic factors that increase susceptibility to MS, the vast majority of which have an immune function. It is also clear that genetics alone are not sufficient to explain every occurrence of MS, exemplified by the fact that only 40% of monozygotic twins are concordant for the disease. Numerous environmental risk factors have been uncovered, including smoking, Epstein-Barr virus infection, and vitamin D deficiency. The latest studies are looking beyond risk, investigating how genetic and environmental factors impact disease progression.

In this podcast, Sergio Baranzini, PhD, The University of California San Francisco, San Francisco, CA, discusses our current knowledge of the etiology of MS, the future of genetic studies, and interesting new findings regarding the gut microbiome and genetic modifiers of MS severity.