1. National Hospital for Neurology and Neurosurgery; MRC Centre for Neuromuscular Diseases; Queen Square London UK
2. CHU Vaudois and University of Lausanne; Nerve-Muscle Unit, Service of Neurology; Lausanne Switzerland 1011
3. Joint Research Office, University College London; UCL School of Life & Medical Sciences; Gower Street London UK WC1E 6BT
4. Great Ormond Street Hospital for Children NHS Trust; Dubowitz Neuromuscular Centre; Great Ormond Street London UK WC1N 3JH