1. Genetic‐Epidemiologic Unit, Department of Clinical Genetics and Department of Epidemiology & Biostatistics, Erasmus MC Rotterdam, The Netherlands
2. University Hospital Carlos J. Finlay, Havana, Cuba
3. Department of Neurology, Adnan Menderes University, Aydin, Turkey
4. Department of Neurology, University of São Paulo, São Paulo, Brazil
5. Neurological Institute IRCCS Mondino, Pavia and A. Avogadro University, Novara, Italy
6. Department of Neuroscience, University of Turin, Turin, Italy
7. Department of Neurology, University of Bari, Bari, Italy
8. Department of Neurology, University of Verona, Verona, Italy
9. Parkinson Institute, Istituti Clinici di Perfezionamento, Milan, Italy
10. Department of Neurological Sciences, University La Sapienza, Rome, Italy
11. Department of Neurology, University of Bologna, Bologna, Italy
12. Neurogenetics Unit, IRCCS Neuromed, Pozzilli, Italy
13. Department of Neurology, University of Florence, Florence, Italy
14. Department of Neurosciences, Ophthalmology and Genetics, University of Genova, Genova, Italy
15. Neurology Division, Hospital Misericordia, Grosseto, Italy
16. Neurology Division, Hospital Boldrini, Thiene, Italy
17. Neurology Division, Hospital of Casarano, Casarano, Italy
18. Neurology Division, INRCA Institute, Ancona, Italy
19. Neurology Division, Hospital of Castrovillari, Castrovillari, Italy
20. Medical Genetics Service, Hospital de Clinicas, Porto Alegre, Brazil
21. Neurology Division, Hospital Piemonte, Messina, Italy
22. Department of Neurology, University of Perugia, Perugia, Italy
23. Division of Neurology, Hospital of Ivrea, Ivrea, Italy
24. National Centre of Epidemiology, National Institute for Health, Rome, Italy
25. Section Medical Genomics, Department of Human Genetics and Department of Biological Psychology, VU University Medical Center, Amsterdam, The Netherlands