1. Department of Neurology; Children's National Medical Center; Washington District of Columbia
2. Child Neuropsychiatry Unit, Department of Brain and Behavioral Sciences; University of Pavia; Pavia Italy
3. Department of Pediatrics; Children's National Medical Center; Washington District of Columbia
4. Division of Neurology; Children's Hospital of Philadelphia; Philadelphia Pennsylvania
5. Division of Child Neurology; Children's Hospital of Pittsburgh of UPMC; Pittsburgh Pennsylvania
6. Department of Genetics; Children's National Medical Center; Washington District of Columbia
7. Neurogenetics Unit, Clinics Hospital of Ribeirao Preto; University of Sao Paulo; Sao Paulo Brazil
8. Medical Genetics Clinic; University of Alberta Hospital; Edmonton Alberta Canada
9. Paediatric Neurology; Starship Children's Hospital; Auckland New Zealand
10. Fundació; Hospital Sant Joan de Deu; Barcelona Spain
11. Klinik und Poliklinik für Kinder- und Jugendmedizin; Uniklinikum Dresden; Dresden Germany
12. Department of Human Genetics; University of Miami Miller School of Medicine; Miami
13. Child Neurology and Psychiatry Unit; C. Mondino National Neurological Institute; Pavia Italy
14. Department of Clinical Genetics; Leiden University Medical Center; Leiden The Netherlands
15. Department of Clinical Genetics; VU University Medical Center; Amsterdam The Netherlands
16. Department of Human Genetics; Radboud University Nijmegen Medical Center; Nijmegen The Netherlands
17. National Institutes of Neurologic Disorders and Stroke; National Institutes of Health; Bethesda Maryland
18. Department of Child Neurology; VU University Medical Center; Amsterdam The Netherlands