1. Institute of Medical Genetics; University of Zürich; Zurich Switzerland
2. Department of Medical Genetics; Oslo University Hospital; Oslo Norway
3. Molecular and Human Genetics; Baylor College of Medicine; Houston Texas
4. Department of Pediatrics; Odense University Hospital; Odense Denmark
5. Department of Clinical Genetics; University Hospital of Copenhagen, Rigshospitalet; Copenhagen Denmark
6. Pediatric Neurology; Children's Hospital; Lucerne Switzerland