1 Unit of Rare Neurodegenerative and Neurometabolic Diseases (C.B., S.F., E.S.), Fondazione IRCCS Istituto Neurologico Carlo Besta; Unit of Medical Genetics and Neurogenetics (S.M., C.C., F.T., D.D.B.), Fondazione IRCCS Istituto Neurologico Carlo Besta; and Unit of Neuroradiology (M.M.), Fondazione IRCCS Istituto Neurologico Carlo Besta, Milano, Italy.