1. Department of Genetic Medicine and Pediatrics Johns Hopkins University Baltimore Maryland
2. Medical Genomics and Metabolic Genetics Branch National Institute of Human Genome Research, National Institutes of Health Bethesda Maryland
3. Division of Pediatric Neurology King Saud bin Abdulaziz University for Health Sciences Riyadh Saudi Arabia
4. King Abdullah International Medical Research Center King Abdullah Specialist Children's Hospital – Ministry of National Guard Riyadh Saudi Arabia
5. Department of Neurology Johns Hopkins University Baltimore Maryland