1 Division of Neurology, Department of Medicine (MLL, HBN, SH, JJSB, HHF), Department of Medical Genetics, Faculty of Medicine (ED), Centre for Applied Neurogenetics, Department of Medical Genetics (MJF, MBM, IG, DME), Division of Neuroradiology, Department of Radiology (JRS), and Department of Ophthalmology and Visual Sciences (JJSB), University of British Columbia, Vancouver, Canada; Department of Geriatric Medicine (ARC), Khoo Teck Puat Hospital, Singapore; and Department of Neuroscience (HHF), University of California San Diego.