1. Department of Neurology, King Abdulaziz Medical City; National Guard Hospital; Riyadh Saudi Arabia
2. Population Genetics, King Abdullah International Medical Research Centre; Riyadh Saudi Arabia
3. Research Unit, Department of Medical Education, College of Medicine; King Saud Bin Abdulaziz University for Health Sciences; Riyadh Saudi Arabia
4. Department of Biochemistry and Molecular Biology; College of Medicine, Alfaisal University; Riyadh Saudi Arabia
5. College of Medicine; King Saud Bin Abdulaziz University for Health Sciences; Riyadh Saudi Arabia