1. Department of Neurodegenerative Disease, UCL Institute of Neurology, Queen Square, London, UK
2. Department of Clinical and Experimental Epilepsy, UCL Institute of Neurology, Queen Square, London, UK
3. UK Dementia Research Institute at UCL, UCL Institute of Neurology, Queen Square, London, UK
4. Cambridge Institute for Medical Research, University of Cambridge, Cambridge, UK
5. Ionis Pharmaceuticals, Carlsbad, California, USA
6. MRC Prion Unit at UCL, Institute of Prion Diseases, Queen Square, London, UK