1. MRC Centre for Neuromuscular diseases; National Hospital for Neurology and Neurosurgery; London UK
2. Neurogenetics Unit; National Hospital for Neurology and Neurosurgery; London UK
3. Service of Neurology; University Hospital “Marqués de Valdecilla (IDIVAL)”, UC and CIBERNED; Santander Spain
4. Department of Neurology; The Walton Centre; Liverpool UK
5. Department of Neurology; Charing Cross Hospital; London UK
6. Department of Clinical Genetics; Royal Devon and Exeter Hospital; Exeter UK
7. Department of Clinical Neurophysiology; Norfolk and Norwich University Hospital; Norwich UK