1. UCL Institute of Neurology and National Hospital for Neurology and Neurosurgery and Great Ormond Street; MRC Centre for Neuromuscular Diseases and Dubowitz Neuromuscular Centre; PO Box 114 London UK WC1B 3BN
2. Medea Scientific Institute; The Conegliano-Pieve Research Centre; Via Costa Alta 37 Conegliano Italy 31015
3. Friedrich-Baur Institute Ludwig-Maximilians University Munich; Department of Neurology; Ziemssenstr. 1a D-80336 Munich Germany