Distribution of African ancestry Index (AAI) for Africans (AFR-green), Amerindians (AMZ-blue) and Europeans (EUR-red) in NMO patients from several Brazilian regions [Southeastern: Ribeirão Preto (NMO-RP), São Paulo (NMO-SP) and Belo Horizonte (NMO-BH); Central:-Goiânia (NMO-GO), and Northeastern: (Recife-Pernambuco (NMO-PE)]; in MS patients from Ribeirão Preto (MS-RP); and in healthy controls from Ribeirão Preto (CTRL-RP).