1. International Parkinson's Centre of Excellence, King's College and King's College HospitalLondon UK
2. Queen Elizabeth Hospital, Woolwich, Lewisham & Greenwich NHS TrustLondon UK
3. Department of Clinical NeurosciencesPsychiatry, Pediatrics and Community Health Sciences, University of CalgaryCalgary Canada
4. Birmingham and Solihull Mental Health National Health Service Foundation Trust, Department of Neuropsychiatry, The Barberry National Centre for Mental HealthBirmingham UK
5. Department of NeuroscienceUniversity of Rome “La Sapienza,”Rome Italy
6. Centre de Reference National Maladie Rare: “Syndrome Gilles de la Tourette,” Departement de Neurologie, Pole des Maladies du Systeme NerveuxParis France
7. Child Study CenterYale UniversityNew Haven Connecticut USA
8. Department of BiostatisticsSchool of Public Health, The University of Texas Health Science Center at HoustonHouston Texas USA
9. Department of Paediatric and Adult Movement Disorders and NeuropsychiatryInstitut of Neurogenetics, University of LübeckLübeck Germany
10. Department of Neurological SciencesRush University Medical CenterChicago Ilinois USA
11. National Center of Epidemiology and Centro Investigación Biomédica en Red Enfermedades Neurodegenerativas, Carlos III Institute of HealthMadrid Spain