[intro music]   Host — Dan Keller Hello, and welcome to Episode Ninety-three of Multiple Sclerosis Discovery, the podcast of the MS Discovery Forum. I’m Dan Keller.   Today's interview features Dr. Lilyana Amezcua, an assistant professor of neurology at the University of Southern California in Los Angeles. Part of her work focuses on defining racial disparities in MS, particularly among the Hispanic community. When we met, she said the prevalence of MS among Hispanics in Latin America has been increasing over the past 20 years, and their clinical characteristics are different from those of whites. As Hispanic Americans constitute one of the largest minorities in the U.S. population, she looked into their clinical picture, as well.   Interviewee – Lilyana Amezcua And so we initially did a first observation in 2011 noting when we examined close to 200 MS patients of Hispanic background self-identified that they were at twice the risk of presenting with optic neuritis and spinal cord problems compared to whites. There is some literature indicating throughout Latin America that these observations could be related to an Asian background. And so when we think about a Hispanic, we think about an umbrella that is related to an intermixing of European, African, and Asian derived background or Native American. So that diversity along with the cultural diversity could have some implications in the way that MS behaves and including risk. And that is one of the theories going around that that's why they don't get MS that much because of an Asian background. However, again, like I mentioned, in the last 20 years more cases have been reported.   Interviewer – Dan Keller Haven't Asians been reported to have this opticospinal sort of MS? So would that feed into this optic neuritis finding with the Hispanics?   Dr. Amezcua That is correct, and actually a second study of ours that we did several years ago was to actually specifically look for that definition of opticospinal MS. And so what we found within 200 or so patients was that indeed when we applied that definition, very few met that criteria. But irrespective of that, and we made sure that every case was negative for aquaporin 4, which is an antibody that you commonly find in more of the NMO spectrum disorders, that these individuals did not have this aquaporin 4, but yet close to 20% looked like they had spinal cord lesions that could be associated with opticospinal.   So that observation, of course, led us to think, well, okay, we should look further. If we do think that Asian ancestry could be important, would some of those clinical characteristics be associated with that type of global ancestry? And in fact today we have a poster related to taking the population that we just presented and looking at their genetic variants, which are mostly noting that the European genetic variants are also found in the Hispanic, but now going forward and looking at, well, what about global ancestry and their clinical characteristics? And in that poster, that abstract, we find that the higher proportion of Asian background you have, the higher risk of presenting with let's say, an optic neuritis. Now that doesn't necessarily say that this is just specific for optic neuritis, but it could going forward let us know about the mechanism behind optic neuritis, which is also found in MS, also found in NMO, and these optical spinal forms of MS.   MSDF How did you go about looking at the genetics of the population?   Dr. Amezcua Going about the genetics actually went back to the fact that when I would say, I'm studying Hispanics, people would ask, what is a Hispanic? And it is true…Hispanic…and so it is defined, you know, when you define it it's well, you can be from Cuba, you can be from Mexico, you can be from the US. But really what links us is…and I sa