Ramil E, S?nchez AJ, Gonz?lez-P?rez P, Rodr?guez-Antig?edad A, G?mez-Lozano N, Ortiz P, Arroyo R, De las Heras V, Vilches C, Garc?a-Merino A. The cannabinoid receptor 1 gene (CNR1) and multiple sclerosis: an association study in two case-control groups from Spain. Mult Scler. 2010 Feb; 16(2):139-46.