1. Department of Molecular Neuroscience, UCL Institute of Neurology, London, UK
2. National Hospital for Neurology and Neurosurgery, Queen Square, London, UK
3. Department of Human Genetics, Radboud University, Nijmegen Medical Centre, Nijmegen, The Netherlands
4. William Harvey Research Institute, Barts and The London School of Medicine and Dentistry, Queen Mary University of London, UK
5. MRC Centre for Neuromuscular Diseases, UCL Institute of Neurology, London, UK