1. Department of Neuroscience, Neurology, Uppsala University Hospital, Uppsala, Sweden
2. Department of Pathology, Gothenburg University, Sahlgrenska Hospital, Göteborg, Sweden
3. Department of Cardiology, Uppsala University Hospital, Uppsala, Sweden
4. Department of Clinical Neurophysiology, Department of Genetics and Pathology, Uppsala University Hospital, Uppsala, Sweden
5. Department of Clinical Genetics, Uppsala University Hospital, Uppsala, Sweden
6. Department of Pathology, Uppsala University Hospital, Uppsala, Sweden
7. Neuromuscular Unit, Linköping University Hospital, Linköping, Sweden