Accepted for Publication: February 1, 2012.
Author Contributions:Study concept and design: Schmidt, Lohmann, Christen, and Klein. Acquisition of data: Schmidt, Kumar, Redyk, Leben, Münchau, Hagenah, Lohmann, Christen, and Klein. Analysis and interpretation of data: Schmidt, Kumar, Grünewald, Leben, Münchau, Sue, Hans, Lohmann, Christen, and Klein. Drafting of the manuscript: Schmidt, Kumar, Grünewald, and Sue. Critical revision of the manuscript for important intellectual content: Schmidt, Kumar, Redyk, Grünewald, Leben, Münchau, Sue, Hagenah, Hans, Lohmann, Christen, and Klein. Obtained funding: Klein. Administrative, technical, and material support: Münchau, Sue, Hans, and Klein. Study supervision: Schmidt, Grünewald, Lohmann, and Klein.
Financial Disclosure: Dr Schmidt receives research support from the medical faculty of the University of Lübeck. Dr Kumar's work is supported by a National Health and Medical Research Council postgraduate scholarship. Dr Grünewald has received research support from the medical faculty of the University of Lübeck, the Deutsche Forschungsgemeinschaft, and the Dystonia Medical Research Foundation. She was also awarded travel grants from the GlaxoSmithKline Foundation, the Boehringer Ingelheim Foundation, and the German Academic Exchange Service. Dr Münchau has received commercial research support by Allergan, Ipsen, and Merz Pharmaceuticals, as well as honoraria for lectures from Allergan. He has also received research support from the Dystonia Medical Research Foundation (USA), the Tourette Society (Germany), and the Deutsche Forschungsgemeinschaft (MU1692/2-2). Dr Sue has received research support from the Australian Brain Foundation. Dr Hagenah receives research support from the Bachmann-Strauss Dystonia and Parkinson Disease Foundation and has received honoraria as an invited speaker from GlaxoSmithKline. Dr Lohmann receives research support from the German Research Foundation and the Bachmann-Strauss Dystonia and Parkinson's Disease Foundation. Dr Klein is a member of the editorial board of Neurology and has served as faculty at the Annual Meetings of the American Academy of Neurology since 2004. She has received consulting fees from Boehringer Ingelheim and Centogene as well as honoraria for speaking engagements from Boehringer Ingelheim and Merz Pharma. Dr Klein is also the recipient of a career development award from the Hermann and Lilly Schilling Foundation. Her work is funded by the Deutsche Forschungsgemeinschaft, the Possehl Foundation, and the Bachmann-Strauss Dystonia and Parkinson's Disease Foundation, and she has received institutional support from the University of Lübeck for genetics research.
Conflicts of Interest: The authors report no conflicts of interest related to the research in this article.
Additional Contributions: We thank the patients and family members for their participation in the study.