1. Department of Neurology; Washington University School of Medicine; Saint Louis Missouri USA
2. Department of Pediatrics; Washington University School of Medicine; Saint Louis Missouri USA
3. Department of Pediatrics; Ohio State University, and the Center for Gene Therapy, Nationwide Children's Hospital; Columbus Ohio USA
4. Department of Neurology; University of Minnesota; Minneapolis Minnesota USA
5. Department of Neurology; Stanford University; Stanford California USA
6. Department Physical Medicine and Rehabilitation; University of California, Davis Medical Center; Sacramento California USA
7. Department of Neurology; Harvard University, Boston Children's Hospital; Boston Massachusetts USA
8. Division of Pediatric Neurology; University of Florida College of Medicine; Gainesville Florida USA
9. Division of Biostatistics; Washington University School of Medicine; Saint Louis Missouri USA