Abstract
Objective:
Age at onset of diagnostic motor manifestations in Huntington disease (HD) is strongly correlated with an expanded CAG trinucleotide repeat. The length of the normal CAG repeat allele has been reported also to influence age at onset, in interaction with the expanded allele. Due to profound implications for disease mechanism and modification, we tested whether the normal allele, interaction between the expanded and normal alleles, or presence of a second expanded allele affects age at onset of HD motor signs.
Methods:
We modeled natural log-transformed age at onset as a function of CAG repeat lengths of expanded and normal alleles and their interaction by linear regression.
Results:
An apparently significant effect of interaction on age at motor onset among 4,068 subjects was dependent on a single outlier data point. A rigorous statistical analysis with a well-behaved dataset that conformed to the fundamental assumptions of linear regression (e.g., constant variance and normally distributed error) revealed significance only for the expanded CAG repeat, with no effect of the normal CAG repeat. Ten subjects with 2 expanded alleles showed an age at motor onset consistent with the length of the larger expanded allele.
Conclusions:
Normal allele CAG length, interaction between expanded and normal alleles, and presence of a second expanded allele do not influence age at onset of motor manifestations, indicating that the rate of HD pathogenesis leading to motor diagnosis is determined by a completely dominant action of the longest expanded allele and as yet unidentified genetic or environmental factors. Neurology® 2012;78:690–695
Huntington disease (HD) is a neurodegenerative disorder with motor impairment, cognitive decline, and psychiatric manifestations1,2 caused by an expanded CAG trinucleotide repeat (>35 CAGs) in the gene encoding huntingtin. The expansion shows a very strong negative correlation with age at onset of motor signs.3–7 Although the dominant inheritance pattern of HD indicates that one expanded allele is sufficient to trigger the disorder, polymorphism of the normal allele CAG repeat (i.e., the number of consecutive CAGs in the nonexpanded allele; <36 CAGs) has been suggested in some but not all studies to influence the timing of onset of disease manifestations.6–9 Recently, an interaction of the expanded and normal allele was reported in a large study to modify age at onset based upon motor signs, cognitive change, and behavioral manifestations.10 Counterintuitively, longer normal alleles (e.g., 30 CAGs) seemingly delayed age at onset of subjects with longer expanded CAG alleles (e.g., >50 CAGs).10 This finding would have important implications for the precise molecular mechanism that initiates HD pathogenesis, as it would suggest that individual huntingtin molecules might physically interact, with a resultant alteration of the pathogenic potential of the expanded repeat. Similarly, if the normal allele can modify HD pathogenesis, it would provide a potential route to therapeutic intervention to delay or prevent onset via a genetic modifier validated to act via a mechanism that operates in humans with HD. Consequently, we re-explored this critical issue using a much larger dataset. Specifically, we aimed to test whether the normal allele CAG repeat, either alone or in interaction with the expanded allele, or the presence of a second expanded allele modifies age at onset of HD motor signs.
METHODS
Subjects.
We analyzed DNA of 4,078 patients with HD (1,864 men, 1,845 women, and 369 unreported) with known age at onset of overt motor manifestations, including 10 subjects with 2 expanded HD alleles (“HD homozygote”). DNA samples were from subjects involved in long-term genetic studies in the Massachusetts HD Center Without Walls, either from the local region or from collaborating investigators (HD-MAPS), and from 3 large HD observational studies (COHORT, PREDICT-HD, and REGISTRY). The HD CAG repeat length was determined using a modification of the PCR amplification assay reported by Warner et al.,9 with a fluorescent oligonucleotide primer pair flanking the repeat for automated allele calling after capillary electrophoresis on an ABI3730XL DNA Analyzer, using a set of HD CAG allele standards determined by DNA sequencing, as reported.11 The means of mutant and normal CAG repeat lengths of HD heterozygote subjects (4,068) were 44.86 (range, 36∼120; median, 44) and 18.48 (range, 9∼35; median, 18), respectively (figure e-1 on the Neurology® Web site at www.neurology.org).
Standard protocol approvals, registrations, and patient consents.
This study used only deidentified, previously collected DNA samples and phenotypic data in a manner approved by the Institutional Review Board of Partners HealthCare, Inc.
Statistical analysis.
Primarily, this study utilized samples from 4,068 HD heterozygote subjects with 1 expanded HD allele. Natural log-transformed age at onset of motor signs was modeled as a function of mutant HD CAG repeat length, normal HD CAG repeat length, and interaction of mutant and normal allele as independent variables using a linear regression analysis. For models involving interaction terms, all continuous variables were centered around the mean value of each variable. Initially, statistical models were fitted to data including all subjects. Subsequently, as described in the supplemental data, we built models using only normally distributed data points in the restricted range of 40 to 53 CAG repeats, where there is no evidence of heteroscedasticity. All statistical analyses were performed using R (version 2.7.2).
RESULTS
Regression analysis of HD heterozygotes.
For all subjects with one expanded HD allele (4,068; figure e-1), the relationship with age at motor onset is shown for both the expanded and normal allele CAG repeat lengths in figure 1, A and B, respectively. For this dataset, we modeled natural log-transformed age at onset by 1) expanded allele CAG repeat length (greater than 35 repeats), 2) normal allele CAG repeat length (35 or fewer repeats), and 3) interaction between them using a linear regression analysis, as has been the common practice in investigation of allele length effects in CAG repeat disorders. Although we initially observed an apparent significant association for the interaction of the normal and mutant alleles, we discovered that this result (table 1) relied on a single outlier with a mutant allele of 120 CAGs and a normal allele of 11 CAGs (shown in blue in figure 1, A and B). That one individual sample could have such a profound effect on the final result indicated that in testing for genetic modifiers, the analysis of HD age-at-onset data requires a more detailed, rigorous statistical analysis that better conforms with the fundamental assumptions of linear regression analysis (normally distributed data points with constant variance). Consequently, we performed a series of statistical analyses to explore this question (figures e-2, e-3, e-4, and e-5), including analysis of subjects with expanded CAG repeats between 40 and 53, with a formal exclusion of outliers, and a separate analysis of the outlier individuals excluded from the model. In no case did we obtain a statistically significant result supporting either an independent effect of the normal CAG repeat or an interaction of the normal and mutant CAG repeats (table 1; table e-1). We also tested directly whether subjects with shorter normal allele CAG repeat lengths had a different age at onset than subjects with longer normal allele CAG repeat lengths (figure e-6), again finding no significant effect of the normal CAG allele on age at onset. Thus, our results indicate that the expanded allele CAG repeat length is the single most important determinant of the age at onset of motor signs of HD and that the normal CAG allele length does not play a significant modifying role in the pathogenic process leading to motor onset.
Table 1.
Statistical analyses of the regression models incorporating expanded and normal CAG alleles and their potential interaction
Loge (age at onset of motor manifestations) ∼ expanded + normal + expanded × normal, using centered variables.
See figure e-5.
Figure 1. Relationship of expanded allele CAG repeat length and age at onset of motor manifestations in individuals with Huntington disease.
An initial regression model was generated using all 4,068 subjects with Huntington disease (HD), each heterozygous for 1 expanded allele (>35 CAG) and 1 allele in the normal range (<36 CAG). (A) The relationship between expanded allele CAG repeat length and age at onset of motor signs. (B) The relationship between normal allele CAG repeat length and age at onset of motor signs. Filled blue circle: a subject with 120 CAGs with a disproportionate influence on the model. (C) Subjects with 2 expanded alleles (>35 CAGs) were plotted (filled red circle: longer expanded allele; green: shorter expanded allele) over the heterozygote subsample conforming to statistical assumptions underlying regression analysis (3,674 HD subjects based upon expanded CAGs from 40–53 and statistical exclusion of outliers; see figures e-3, e-4, and e-5). One homozygous subject has 2 equal alleles of 42 CAGs. The minimal adequate model for this heterozygote data set is shown as a red line.
HD “homozygotes.”
Importantly, in addition to the heterozygote subjects analyzed above, there were 10 subjects with 2 expanded alleles in our dataset. Although the sample size is small, these subjects would have the potential to reveal any major additive or synergistic effects of possessing 2 expanded alleles and no normal allele. There is clearly no additive effect, as all of these individuals would be expected to show motor onset at <4 years of age if this were determined by the sum of the 2 expanded CAG repeats. Interestingly, subjects with 2 expanded alleles (figure 1C; red, longer allele; green, shorter allele) did not show a significant deviation from the minimal adequate statistical model (from figure e-5 data) when plotted based upon the longer of their 2 expanded alleles (figure 1C, red line). The ages at onset of these subjects resided within 2 standard deviations of each allele-specific age at onset spectrum. Combined with our findings from HD heterozygotes, these data indicate that age at onset of motor manifestations in HD is primarily determined by a single allelic dose of the mutant gene and is not influenced dramatically by the length of the normal allele, by the presence of a second mutant allele, or by the absence of a normal allele.
DISCUSSION
It is well known that HD is initiated by a dominant action of an expanded CAG repeat in the HD gene and that age at onset strongly correlates with expanded allele CAG repeat length. However, there has been much debate in the field whether age at onset is influenced by the second HD allele, especially the length of the CAG repeat on the normal chromosome.6–10,12–15 This is a critical question, as the answer determines whether the pathogenic effect of the expanded polyglutamine tract in mutant huntingtin protein can be modulated by expression of an equivalent huntingtin protein with a polyglutamine repeat in the normal size range. A positive finding would clearly have ramifications both for the current effort to develop a therapy by nonselective RNA-mediated suppression of mutant and normal HD alleles and also for the potential of using wild-type huntingtin as a therapeutic protein in HD.
Using the largest dataset so far, with stringent statistical analyses, our results have dismissed a significant role for the normal allele CAG repeat length in modifying age at onset of motor manifestations, indicating that the expanded allele CAG repeat length is not only the initial trigger of HD pathogenesis but also the predominant factor determining the rate of the process that leads to motor onset. We found no evidence that an interaction between the expanded allele and the normal allele is an explanation for any portion of the variance in age at onset of motor signs that is not already explained by the expanded allele alone. Furthermore, our findings with a larger series of CAG repeat genotyped HD homozygotes support previous reports that, at lengths over 40 repeats (repeats <40 may show nonpenetrance), a single allelic dose of the HD mutation is sufficient to cause HD within a typical human lifespan and to determine age at motor onset.16–21 Though the 10 homozygotes studied are too few to exclude any onset-modifying effect of the second mutant allele on a statistical basis, any such effect would have to be quite small compared to the effect of the single mutant allele discerned in HD heterozygotes. This suggests that the level of mutant huntingtin protein produced from a single allele already exceeds any minimum threshold required to trigger pathogenesis (at a rate determined primarily by its CAG repeat length) and that neither additional mutant protein nor the absence of any normal protein further alters the rate of pathogenesis leading to motor onset.
Although our results clearly showed no effect of the normal allele CAG repeat length on age at onset, other cis-factors may play a role in modifying age at onset. For example, a gene closely linked to the HD gene has been hypothesized to modify age at onset14 and, in the HD-MAPS study, suggestive evidence for linkage was found at chromosome 4p16.22 Therefore, it also will be important to determine a potential role for other cis-factors in potentially modifying age at onset of HD manifestations. In addition, although neither the normal HD CAG allele repeat length nor its interaction with the expanded allele influenced age at motor onset, the remaining variance has been reported to be highly heritable,12,15 indicating the presence in the genome of genetic modifiers. Such modifier genes would provide potential therapeutic targets already validated to alter the course of HD in human patients and so their identification is a very active area of investigation. The findings reported here provide the basis for more reliable statistical assessment of the role of individual modifier genes and should contribute to their unequivocal identification.
Supplementary Material
ACKNOWLEDGMENT
The authors thank the study participants and their families, who made this work possible, coinvestigators and contributors from the HD-MAPS study, the Huntington Study Group PREDICT-HD and COHORT studies, and the European Huntington's Disease Network REGISTRY study (see appendix e-1) as well as the National Research Roster for Huntington Disease Patients and Families.
GLOSSARY
- HD
Huntington disease
Footnotes
Editorial, page 686
Supplemental data at www.neurology.org
Coinvestigators and Contributors are listed on the Neurology® Web site at www.neurology.org.
Contributor Information
Alexandra Durr, INSERM Hôpital de la Salpêtriére, Paris, France, HD-MAPS Investigator.
Adam Rosenblatt, Johns Hopkins University, USA, HD-MAPS Investigator.
Luigi Frati, University La Sapienza, Rome, Italy, HD-MAPS Investigator.
Susan Perlman, University of California Los Angeles, USA, HD-MAPS Investigator.
Patrick M. Conneally, Indiana University School of Medicine, USA, HD-MAPS Investigator.
Mary Lou Klimek, University of Calgary, Canada, HD-MAPS Coordinator.
Melissa Diggin, Boston University School of Medicine/Boston Medical Center, USA, HD-MAPS Coordinator.
Tiffany Hadzi, Boston University School of Medicine/Boston Medical Center, USA, HD-MAPS Coordinator.
Ayana Duckett, Columbia University Medical Center, USA, HD-MAPS Coordinator.
Anwar Ahmed, Cleveland Clinic Foundation, Cleveland, Ohio, USA, Site Investigator.
Paul Allen, University of Iowa, Core IT/Management Section.
David Ames, The University of Melbourne, Kew, Victoria, Australia, Site Investigator.
Christine Anderson, University of Iowa, Core Recruitment/Retention Section.
Karla Anderson, University of Iowa, Program Management: Administrative.
Karen Anderson, University of Maryland, Psychiatric Section.
Thomasin Andrews, National Hospital for Neurology and Neurosurgery, London, UK, Site Staff.
John Ashburner, Functional Imaging Lab, London, Imaging Section: Administrative.
Eric Axelson, University of Iowa, Imaging Section: Administrative and Surface Analysis.
Elizabeth Aylward, Seattle Children's Research Institute, Steering Committee and Imaging Section: Striatal Chair.
Roger A. Barker, Cambridge Centre for Brain Repair, Cambridge, UK, Site Investigator.
Katrin Barth, University of Ulm, Ulm, Germany, Site Staff.
Stacey Barton, Washington University, St. Louis, Missouri, USA, Site Staff.
Kathleen Baynes, University of California Davis, Sacramento, California, USA,Site Investigator.
Alexandra Bea, Cleveland Clinic Foundation, Cleveland, Ohio, USA, Site Staff.
Erik Beall, Cleveland Clinic, Imaging Section: fMRI.
Mirza Faisal Beg, Simon Fraser University, Imaging Section: Shape Analysis.
Leigh J. Beglinger, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Cognitive and Functional Assessment Sections.
Kevin Biglan, University of Rochester, Steering Committee and Motor Section co-Chair.
Kristine Bjork, University of Iowa, Program Management: Administrative.
Steve Blanchard, University of Iowa, Program Management: Financial, Co-Chair.
Jeremy Bockholt, University of Iowa, Imaging Section: Surface Analysis.
Sudharshan Reddy Bommu, University of Iowa, Core IT/Management Section.
Bradley Brossman, University of Iowa, Functional Assessment Section.
Maggie Burrows, National Hospital for Neurology and Neurosurgery, London, UK, Site Staff.
Vince Calhoun, University of New Mexico, Imaging Section: Administrative.
Noelle Carlozzi, Kessler Medical Rehabilitation Research & Education Center, Functional Assessment Section,.
Amy Chesire, University of Rochester, Rochester, New York, USA, Site Staff.
Edmond Chiu, The University of Melbourne, Kew, Victoria, Australia, Site Investigator.
Phyllis Chua, The University of Melbourne, Kew, Victoria, Australia, Site Investigator.
R.J. Connell, University of Iowa, Core IT/Management Section.
Carmela Connor, Neurosciences Unit, Graylands, Selby-Lemnos & Special Care Health Services, Perth, Australia, Site Staff.
Jody Corey-Bloom, University of California, San Diego, Motor Section co-Chair.
David Craufurd, University of Manchester, UK, Site Investigator and Psychiatric Section.
Stephen Cross, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Site Staff.
Lucette Cysique, St. Vincent's/University of Melbourne, Australia, Cognitive Section.
Rachelle Dar Santos, University of British Columbia, Vancouver, British Columbia, Canada, Site Staff.
Jennifer Davis, Scientific Consultants, Alpert Medical School of Brown University, Cognitive Section.
Joji Decolongon, University of British Columbia, Vancouver, British Columbia, Canada, Site Staff.
Anna DiPietro, Cambridge Centre for Brain Repair, Cambridge, UK, Site Staff.
Nicholas Doucette, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Core Recruitment/Retention Section.
Nancy Downing, University of Iowa, Psychiatric Section.
Ann Dudler, University of Iowa, Program Management: Administrative.
Steve Dunn, University of Iowa; Imaging Section: Administrative.
Daniel Ecker, University of Ulm, Ulm, Germany, Site Investigator.
Eric A. Epping, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Steering Committee, Psychiatric Section Chair and Core Ethics Section.
Diane Erickson, Colorado Neurological Institute, Englewood, Colorado, USA, Site Staff.
Cheryl Erwin, McGovern Center for Health, Humanities and the Human Spirit, Core Ethics Section Chair.
Ken Evans, Ontario Cancer Biomarker Network, BioMarkers and Psychiatric Sections.
Stewart A. Factor, Emory University School of Medicine, Atlanta, Georgia, USA, Site Investigator.
Sarah Farias, University of California, Davis, Functional Assessment Section.
Marta Fatas, Hospital Ramón y Cajal, Madrid, Spain, Site Staff.
Jess Fiedorowicz, University of Iowa, Psychiatric Section.
Ruth Fullam, University of Manchester, Manchester, UK, Site Staff.
Sarah Furtado, University of Calgary, Calgary, Alberta, Canada, Site Investigator.
Monica Bascunana Garde, Hospital Ramón y Cajal, Madrid, Spain, Site Staff.
Carissa Gehl, VA Medical Center, Iowa City, IA, Cognitive and Functional Assessment Sections.
Michael D. Geschwind, University of California San Francisco, California, USA, Site Investigator and Motor Section.
Anita Goh, The University of Melbourne, Kew, Victoria, Australia, Site Staff.
Jon Gooblar, University of California San Francisco, California, USA, Site Staff.
Anna Goodman, Cambridge Centre for Brain Repair, Cambridge, UK, Site Staff.
Jane Griffith, Westmead Hospital, Sydney, Australia, Site Staff.
Mark Groves, Columbia University, Psychiatric Section.
Mark Guttman, Centre for Addiction and Mental Health, University of Toronto, Markham, Ontario, Canada, Site Investigator.
Joanne Hamilton, University of California, San Diego, Cognitive Section.
Deborah Harrington, University of California, San Diego, Cognitive Section Chair.
Greg Harris, University of Iowa, Imaging Section: Administrative.
Robert K. Heaton, University of California, San Diego, Cognitive Section.
Karl Helmer, Massachusetts General Hospital, Imaging Section: DTI.
Machelle Henneberry, University of Iowa, Program Management: Financial.
Tamara Hershey, Washington University Cognitive Science Battery Development, Cognitive Section.
Kelly Herwig, University of Iowa, Core Recruitment/Retention Section.
Elizabeth Howard, University of Manchester, Manchester, UK, Site Investigator.
Christine Hunter, Baylor College of Medicine, Houston, Texas, USA, Site Staff.
Joseph Jankovic, Baylor College of Medicine, Houston, Texas, USA, Site Investigator.
Hans Johnson, University of Iowa Hospitals and Clinics, Iowa City, IA, Steering Committee and Core IT/Management Section Chair.
Arik Johnson, University of California, Los Angeles Medical Center, Los Angeles, California, USA, Site Investigator.
Kathy Jones, University of Iowa, Imaging Section: Administrative.
Andrew Juhl, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Site Staff.
Eun Young Kim, University of Iowa, Imaging Section: Administrative.
Mycah Kimble, University of Iowa, Core Recruitment/Retention Section.
Pamela King, University of Alberta, Edmonton, Alberta, Canada, Site Staff.
Mary Lou Klimek, University of Calgary, Calgary, Alberta, Canada, Site Coordinator.
Stefan Klöppel, National Hospital for Neurology and Neurosurgery, London, UK, Site Investigator.
Katherine Koenig, Cleveland Clinic, Imaging Section: fMRI.
Angela Komiti, The University of Melbourne, Kew, Victoria, Australia, Site Staff.
Rajeev Kumar, Colorado Neurological Institute, Englewood, Colorado, USA, Site Investigator.
Douglas Langbehn, University of Iowa, Steering Committee and Core Statistics Section Chair.
Blair Leavitt, University of British Columbia, Steering Committee and BioMarkers Section Chair.
Anne Leserman, University of Iowa, Functional Assessment and Core Recruitment/Retention Sections.
Kelvin Lim, University of Ulm, Germany, Imaging Section: DTI.
Hillary Lipe, University of Washington and VA Puget Sound Health Care System, Seattle, Washington, USA, Site Staff.
Mark Lowe, Cleveland Clinic, Imaging Section: fMRI and DTI.
Vincent A. Magnotta, University of Iowa, Imaging Section: DTI Chair.
William M. Mallonee, Hereditary Neurological Disease Centre, Wichita, Kansas, USA, Site Investigator.
Nicole Mans, University of California Davis, Sacramento, California, USA, Site Staff.
Jacquie Marietta, University of Iowa, Imaging Section: Administrative.
Frederick Marshall, University of Rochester, Rochester, New York, USA, Site Investigator.
Wayne Martin, University of Alberta, Edmonton, Alberta, Canada, Site Investigator.
Sarah Mason, Cambridge Centre for Brain Repair, Cambridge, UK, Site Staff.
Kirsty Matheson, University of Aberdeen, Cognitive Section.
Wayne Matson, VA Medical Center, Bedford, MA, BioMarkers Section.
Pietro Mazzoni, Columbia University Medical Center, New York, New York, USA, Site Investigator.
William McDowell, University of Iowa, Imaging Section: Administrative.
Zosia Miedzybrodzka, Clinical Genetics Centre, Aberdeen, Scotland, UK, Site Investigator.
Michael Miller, Johns Hopkins University, Imaging Section: Shape Analysis.
James Mills, University of Iowa, Core Statistics Section.
Dawn Miracle, Colorado Neurological Institute, Englewood, Colorado, USA, Site Staff.
Kelsey Montross, University of Iowa, Program Management: Financial.
David Moore, University of California, San Diego, Cognitive Section.
Sasumu Mori, Johns Hopkins University, Imaging Section: DTI.
David J. Moser, University of Iowa, Cognitive Section.
Carol Moskowitz, Columbia University Medical Center, New York, New York, USA, Site Coordinator.
Emily Newman, Cleveland Clinic Foundation, Cleveland, Ohio, USA.
Peg Nopoulos, University of Iowa, Imaging Section: Surface Analysis Chair.
Marianne Novak, National Hospital for Neurology and Neurosurgery, London, UK, Site Investigator.
Justin O'Rourke, University of Iowa, Functional Assessment Section.
David Oakes, University of Rochester, Core Statistics Section.
William Ondo, Baylor College of Medicine, Houston, Texas, USA, Site Investigator.
Michael Orth, University of Ulm, Ulm, Germany, Site Investigator.
Peter Panegyres, Neurosciences Unit, Graylands, Selby-Lemnos & Special Care Health Services, Perth, Australia, Site Investigator.
Karen Pease, University of Iowa, Core IT/Management Section.
Susan Perlman, University of California, Los Angeles Medical Center, Los Angeles, California, USA, Site Investigator.
Joel Perlmutter, Washington University, St. Louis, Missouri, USA, Site Investigator.
Asa Peterson, Lund University, Sweden, BioMarkers Section.
Michael Phillips, Cleveland Clinic, Imaging Section: fMRI.
Ron Pierson, University of Iowa, Imaging Section: Administrative Chair.
Steve Potkin, University of California, Irvine, Imaging Section: Administrative.
Joy Preston, The University of Melbourne, Kew, Victoria, Australia, Site Staff.
Kimberly Quaid, Indiana University School of Medicine, Indianapolis, IN, Site Investigator.
Dawn Radtke, Hennepin County Medical Center, Minneapolis, Minnesota, USA, Site Coordinator.
Daniela Rae, Clinical Genetics Centre, Aberdeen, Scotland, UK, Site Staff.
Stephen Rao, Cleveland Clinic Foundation, Cleveland, Ohio, USA, Site Investigator and Imaging Section: fMRI Chair.
Lynn Raymond, University of British Columbia, Vancouver, British Columbia, Canada, Site Investigator.
Sarah Reading, Johns Hopkins University, Imaging Section: Shape Analysis.
Rebecca Ready, University of Massachusetts, Functional Assessment Section.
Christine Reece, Cleveland Clinic, Site Coordinator and Imaging Section: fMRI.
Ralf Reilmann, Muenster, Germany, Motor Section.
Norm Reynolds, University of Wisconsin, Milwaukee, Core Recruitment/Retention Section.
Kylie Richardson, Westmead Hospital, Sydney, Australia, Site Staff.
Hugh Rickards, Queen Elizabeth Psychiatric Hospital, Psychiatric Section.
Eunyoe Ro, University of Iowa, Functional Assessment Section.
Robert Robinson, University of Iowa, Psychiatric Section.
Robert Rodnitzky, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Site Investigator.
Ben Rogers, University of Iowa, Core IT/Management Section.
Adam Rosenblatt, Johns Hopkins University, Baltimore, Maryland, USA, Site Investigator.
Elisabeth Rosser, National Hospital for Neurology and Neurosurgery, London, UK, Site Investigator.
Kathy Price, Cardiff University, Cardiff, Wales, UK, Site Investigator.
Kathy Price, Cardiff University, Cardiff, Wales, UK, Site Coordinator.
Pat Ryan, University of Iowa, Core Recruitment/Retention Section.
David Salmon, University of California, San Diego, Cognitive Section.
Ali Samii, University of Washington and VA Puget Sound Health Care System, Seattle, Washington, USA, Site Investigator.
Jamy Schumacher, University of Iowa, Program Management: Administrative.
Jessica Schumacher, University of Iowa, Core Recruitment/Retention Section.
Jose Luis Lópenz Sendon, Hospital Ramón y Cajal, Madrid, Spain, Site Investigator.
Paula Shear, University of Cincinnati, Cognitive Section.
Alanna Sheinberg, Centre for Addiction and Mental Health, University of Toronto, Markham, Ontario, Canada, Site Staff.
Barnett Shpritz, Johns Hopkins University, Baltimore, Maryland, USA, Site Staff.
Karen Siedlecki, Fordham University, Cognitive Section.
Sheila A. Simpson, Clinical Genetics Centre, Aberdeen, Scotland, UK, Site Investigator.
Adam Singer, Centre for Addiction and Mental Health, University of Toronto, Markham, Ontario, Canada, Site Staff.
Jim Smith, University of Iowa, Core IT/Management Section.
Megan Smith, University of Iowa Hospitals and Clinics, Iowa City, IA Steering Committee, Cognitive Section: Chair Administration and Psychiatric Section.
Glenn Smith, Mayo Clinic, Cognitive Section.
Pete Snyder, Scientific Consultants, Alpert Medical School of Brown University, Cognitive Section.
Allen Song, Duke University, Imaging Section: DTI, Site Staff.
Satwinder Sran, University of Alberta, Edmonton, Alberta, Canada.
Klaas Stephan, University College of London, Imaging Section: Administrative.
Janice Stober, Centre for Addiction and Mental Health, University of Toronto, Markham, Ontario, Canada, Site Staff.
Sigurd Sü?muth, University of Ulm, Ulm, Germany, Site Staff.
Greg Suter, Hereditary Neurological Disease Centre, Wichita, Kansas, USA, Site Coordinator.
Sarah Tabrizi, National Hospital for Neurology and Neurology and Neurosurgery, London, Site Investigator and BioMarkers Section.
Terry Tempkin, University of California Davis, Sacramento, California, USA, Site Coordinator.
Claudia Testa, Emory University School of Medicine, Atlanta, Georgia, USA, Site Investigator.
Sean Thompson, University of Iowa, Program Management: Administrative.
Teri Thomsen, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Site Investigator.
Kelli Thumma, University of Iowa, Core Recruitment/Retention Section.
Arthur Toga, University of California, Los Angeles, Imaging Section: Administrative.
Sonja Trautmann, University of Ulm, Ulm, Germany, Site Staff.
Geoff Tremont, Scientific Consultants, Alpert Medical School of Brown University, Cognitive Section.
Jessica Turner, University of California, Irvine, Imaging Section: DTI.
Ergun Uc, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Site Investigator.
Anthony Vaccarino, Ontario Cancer Biomarker Network, Psychiatric and Functional Assessment Sections.
Eric van Duijn, Leiden University Medical Center, Netherlands, Psychiatric Section.
Marleen Van Walsem, Rikshospitalet, Oslo, Norway, Cognitive Section.
Stacie Vik, University of Iowa, Core Recruitment/Retention Section.
Jean Paul Vonsattel, Columbia University Medical Center, New York, NY, Steering Committee.
Elizabeth Vuletich, Neurosciences Unit, Graylands, Selby-Lemnos & Special Care Health Services, Perth, Australia, Site Staff.
Tom Warner, National Hospital for Neurology and Neurosurgery, London, UK, Site Investigator.
Paula Wasserman, Columbia University Medical Center, New York, New York, USA, Site Staff.
Thomas Wassink, University of Iowa, Site Investigator and Genetics Section, Co-Chair.
Elijah Waterman, University of Iowa, Core Recruitment/Retention Section.
Kurt Weaver, University of Washington and VA Puget Sound Health Care System, Seattle, Washington, USA, Site Investigator and Imaging Section: Striatal.
David Weir, University of British Columbia, Vancouver, British Columbia, Canada, Site Staff.
Claire Welsh, Johns Hopkins University, Baltimore, Maryland, USA,Site Staff.
Chris Werling-Witkoske, University of Iowa, Program Management: Administrative, Chair.
Melissa Wesson, Indiana University School of Medicine, Indianapolis, IN, Site Staff.
Holly Westervelt, Alpert Medical School of Brown University, Cognitive Section Chair, Quality Control and Training.
Patrick Weydt, University of Ulm, Ulm, Germany, Site Investigator.
Vicki Wheelock, University of California Davis, Sacramento, California, USA, Site Investigator.
Kent Williams, University of Iowa, Core IT/Management Section.
Janet Williams, University of Iowa, Steering Committee, Functional Assessment Section, Co-Chair and Core Ethics Section.
Mary Wodarski, University of Rochester, Rochester, New York, USA, Site Staff.
Joanne Wojcieszek, Indiana University School of Medicine, Indianapolis, IN, Site Investigator.
Jessica Wood, University of Iowa Hospitals and Clinics, Iowa City, Iowa, USA, Site Investigator.
Cathy Wood-Siverio, Emory University School of Medicine, Atlanta, Georgia, USA, Site Staff.
Shuhua Wu, University of Iowa, Core IT/Management Section.
Olga Yastrubetskaya, The University of Melbourne, Kew, Victoria, Australia, Site Investigator.
Justo Garcia de Yebenes, Hospital Ramón y Cajal, Madrid, Spain, Site Investigator.
Yong Qiang Zhao, University of Iowa, Imaging Section: Administrative.
Janice Zimbelman, Cleveland Clinic, Imaging Section: fMRI.
Roland Zschiegner, University of Iowa, Core IT/Management Section.
Olaf Aaserud, Oslo University Hospital (Rikshospitalet.
Giovanni Abbruzzese, Università di Genova, Italy, Site Investigator.
Thomasin Andrews, The National Hospital for Neurology and Neurosurgery, London, UK, Site Investigator.
Jurgin Andrich, Huntington-Zentrum (NRW.
Jakub Antczak, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Site Investigator.
Natalie Arran, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Staff.
Maria J. Saiz Artiga, Madrid-Fundación Jiménez Díaz, Spain, Site Staff.
Anne-Catherine Bachoud-Lévi, Centre de référence maladie de Huntington, Groupe Hospitalier Chenevier-Mondor, Créteil, France, Steering Committee.
Krysztof Banaszkiewicz, Krakowska Akademia Neurologii, Poland, Site Investigator.
Monica Bandettini di Poggio, Università di Genova, Italy, Site Investigator.
Oliver Bandmann, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Investigator.
Miguel A. Barbera, Hospital Mútua de Terrassa Barcelona, Spain, Site Staff
Roger A. Barker, Cambridge Centre for Brain Repair, UK, Site Investigator.
Francisco Barrero, Hospital Universitario San Cecili, Spain, Site Staff.
Katrin Barth, Universitätsklinikum Ulm, Germany, Steering Committee and Site Staff.
Jordi Bas, Hospital Universitari de Bellvitge Barcelona, Spain, Site Investigator.
Antoine Beister, Universitätsklinikum Münster, Germany, Site Staff.
Anna Rita Bentivoglio, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Steering Committee and Site Investigator.
Elisabetta Bertini, Universita' degli Studi di Firenze /Azienda Ospedaliera, Italy, Site Staff.
Ida Biunno, Consiglio Nazionale delle Ricerche, Italy, Steering Committee.
Kathrine Bjørgo, Oslo University Hospital (Ulleval.
Inga Bjørnevoll, St. Olavs Hospital Trondheim, Norway, Site Investigator.
Stefan Bohlen, Universitätsklinikum Münster, Germany, Site Staff.
Raphael M. Bonelli, LKH Graz Abteilung für Psychiatrie, Austria, Steering Committee and Site Investigator.
Reineke Bos, Leiden University Medical Centre, Netherlands, Site Coordinator and Language coordinator.
Colin Bourne, Leicestershire Partnership Trust Mill Lodge, UK, Site Staff.
Alyson Bradbury, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Staff.
Peter Brockie, Scottish Huntington's Association Whyteman's Brae Hospital Fife, UK, Site Staff.
Felicity Brown, Abercromby Center Glasgow, UK, Site Staff.
Stefania Bruno, The National Hospital for Neurology and Neurosurgery, London, UK, Site Staff.
Anna Bryl, Medical University of Poznan, Poland, Site Investigator.
Andrea Buck, Universitätsklinikum Ulm, Germany, Site Staff.
Sabrina Burg, Universitätsklinikum Ulm, Germany, Language coordinator.
Jean-Marc Burgunder, Swiss HD Centre Gümligen Bern, Switzerland, Steering Committee and Site Investigator.
Peter Burns, Gloucestershire Royal Hospital, UK, Site Staff.
Liz Burrows, Abercromby Center Glasgow, UK, Site Staff.
Nuria Busquets, Hospital Universitari de Bellvitge Barcelona, Spain, Site Staff.
Monica Busse, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Staff.
Matilde Calopa, Hospital Universitari de Bellvitge Barcelona, Spain, Site Staff.
Gemma T. Carruesco, Hospital Mútua de Terrassa Barcelona, Spain, Site Staff
Ana Gonzalez Casado, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Judit López Catena, Hospital Mútua de Terrassa Barcelona, Spain, Site Staff.
Carol Chu, Castle Hill Hospital Hull and Chapel Allerton Hospital Leeds, UK, Site Staff.
Anna Ciesielska, Medical University of Poznan, Poland, Site Staff.
Jackie Clapton, Leicestershire Partnership Trust Mill Lodge, UK, Site Staff.
Carole Clayton, Leicestershire Partnership Trust Mill Lodge, UK, Site Coordinator.
Catherine Clenaghan, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Staff.
Miguel Coelho, Hospital de Santa Maria/Instituto de Medicina Molecular Lisbon, Portugal, Site Staff.
Julia Connemann, Universitätsklinikum Ulm, Germany, Site Staff.
David Craufurd, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Investigator.
Jenny Crooks, The Barberry Centre Birmingham, UK, Site Staff.
Patricia Trigo Cubillo, Hospital Ramón y Cajal Madrid, Spain, Language coordinator.
Esther Cubo, Hospital General Yagüe Burgos Granada, Spain, Site Investigator.
Adrienne Curtis, The Barberry Centre Birmingham, UK, Site Investigator.
Giuseppe De Michele, Azienda Ospedaliera Universitaria Federico II Naples, Italy, Site Investigator.
A. De Nicola, Neurogenetics and Rare Disease Centre Pozzilli, Italy, Site Staff
Jenny de Souza, Keylock.
A. Marit de Weert, Polikliniek Neurologie Groningen, Netherlands, Site Staff.
Justo Garcia de Yébenes, Hospital Ramón y Cajal Madrid, Spain, Site Investigator.
M. Dekker, Polikliniek Neurologie Groningen, Netherlands, Site Investigator.
A. Martínez Descals, Fundación Jiménez Díaz, Madrid, Spain, Language coordinator.
Luigi Di Maio, Azienda Ospedaliera Universitaria Federico II Naples, Italy, Site Investigator.
Anna Di Pietro, Cambridge Centre for Brain Repair, UK, Site Staff.
Heather Dipple, Leicestershire Partnership Trust Mill Lodge, UK, Site Staff.
Matthias Dose, Isar-Amper-Klinikum Taufkirchen, Germany, Site Investigator.
Eve M. Dumas, Leiden University Medical Centre, Netherlands, Site Staff
Stephen Dunnett, The Institute of Medical Genetics/University Hospital of Wales, UK, Steering Committee.
Daniel Ecker, Universitätsklinikum Ulm, Germany, Site Staff.
F. Elifani, Neurogenetics and Rare Disease Centre Pozzilli, Italy, Site Staff
Lynda Ellison-Rose, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Staff.
Marina D. Elorza, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff
Carolin Eschenbach, Universitätsklinikum Ulm, Germany, Site Coordinator.
Carole Evans, Castle Hill Hospital Hull, UK, Site Staff.
Helen Fairtlough, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Staff.
Madelein Fannemel, Oslo University Hospital (Ulleval.
Alfonso Fasano, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Staff.
Maria Fenollar, Hospital Clínico Universitario San Carlos Madrid-Clinico, Spain, Site Staff.
Giovanna Ferrandes, Università di Genova, Italy, Site Investigator.
Jaoquim J. Ferreira, Hospital de Santa Maria/Instituto de Medicina Molecular Lisbon, Portugal, Steering Committee and Site Investigator
Kay Fillingham, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Staff.
Ana Maria Finisterra, Portugal, Language coordinator.
K. Fisher, Cambridge Centre for Brain Repair, UK, Site Staff
Amy Fletcher, Gloucestershire Royal Hospital, UK, Site Staff.
Jillian Foster, Scottish Huntington's Association Whyteman's Brae Hospital Fife, UK, Site Coordinator.
Isabella Foustanos, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Staff.
Fernando A. Frech, Madrid-Fundación Jiménez Díaz, Spain, Site Staff
Robert Fullam, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Staff.
Ruth Fullham, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Staff.
Miguel Gago, Faculdade de Medicina da Universidade do Porto/Hospital de São João, Portugal, Site Investigator.
RocioGarcía-Ramos García, Hospital Clínico Universitario San Carlos Madrid-Clinico, Spain, Site Staff.
Socorro S. García, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff
Carolina Garrett, Faculdade de Medicina da Universidade do Porto/Hospital de São João, Portugal, Site Investigator.
Cinzia Gellera, Fondazione IRCCS Istituto Neurologico Carlo Besta Milan, Italy, Site Staff.
Paul Gill, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Staff.
Andrea Ginestroni, Universita' degli Studi di Firenze /Azienda Ospedaliera, Italy, Site Staff.
Charlotte Golding, The National Hospital for Neurology and Neurosurgery, London, UK, Site Staff.
Anna Goodman, Cambridge Centre for Brain Repair, UK, Site Staff.
Per Gørvell, Oslo University Hospital (Ulleval).
Janet Grant, Leicestershire Partnership Trust Mill Lodge, UK, Site Investigator.
A. Griguoli, Neurogenetics and Rare Disease Centre Pozzilli, Italy, Site Staff
Diana Gross, Leicestershire Partnership Trust Mill Lodge, UK, Site Investigator.
Leonor Guedes, Hospital de Santa Maria/Instituto de Medicina Molecular Lisbon, Portugal, Language coordinator.
Monica BascuñanaGuerra, Hospital Ramón y Cajal Madrid, Spain, Language coordinator.
Maria Rosalia Guerra, Faculdade de Medicina da Universidade do Porto/Hospital de Sao Joao, Portugal, Site Staff.
Rosa Guerrero, Madrid-Fundación Jiménez Díaz, Spain, Site Staff.
Dolores B. Guia, Hospital Mútua de Terrassa Barcelona, Spain, Site Staff
Arianna Guidubaldi, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Staff.
Caroline Hallam, Leicestershire Partnership Trust Mill Lodge, UK, Site Staff.
Stephanie Hamer, Castle Hill Hospital Hull, UK, Site Staff.
Kathrin Hammer, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Olivia J. Handley, University College London, UK, Steering Committee and Language Coordinator
Alison Harding, Gloucestershire Royal Hospital, UK, Site Staff.
Lis Hasholt, Hukommelsesklinikken Rigshospitalet Panum Instituttet Copenhagen, Denmark, Site Investigator.
Reikha Hedge, Abercromby Center Glasgow, UK, Site Staff.
Arvid Heiberg, Oslo University Hospital (Rikshospitalet).
Walburgis Heinicke, Psychatrium Heiligenhafen, Germany, Site Investigator.
Christine Held, Universitätsklinikum Ulm, Germany, Language coordinator.
Laura Casas Hernanz, Hospital Mútua de Terrassa Barcelona, Spain, Site Staff.
Briggitte Herranhof, LKH Graz Abteilung für Psychiatrie, Austria, Site Staff.
Carmen Durán Herrera, Hospital Infanta Cristina Badajoz, Spain, Site Staff.
Ute Hidding, Universitätsklinikum Hamburg-Eppendorf/Klinik und Poliklinik für, Germany, Site Staff.
Heli Hiivola, Rehabilitation Centre Suvituuli Turku-Suvituuli, Finland, Site Staff.
Susan Hill, Cambridge Centre for Brain Repair, UK, Site Staff.
Lena. E. Hjermind, Hukommelsesklinikken Rigshospitalet Panum Instituttet Copenhagen, Denmark, Site Staff
Emma Hobson, Chapel Allerton Hospital Leeds, UK, Site Staff.
Rainer Hoffmann, Huntington-Zentrum (NRW).
Anna Hödl Holl, LKH Graz Abteilung für Psychiatrie, Austria, Site Investigator.
Liz Howard, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Investigator.
Sarah Hunt, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Staff.
Susan Huson, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Investigator.
Tamara Ialongo, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Staff.
Jesus Miguel R. Idiago, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff
Torsten Illmann, EHDN Central Coordination, Germany, Steering Committee.
Katarzyna Jachinska, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Site Investigator.
Gioia Jacopini, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Investigator.
Oda Jakobsen, Hukommelsesklinikken Rigshospitalet Panum Instituttet Copenhagen, Denmark, Site Staff.
Stuart Jamieson, Chapel Allerton Hospital Leeds, UK, Site Staff.
Zygmunt Jamrozik, Medical University of Warsaw, Poland, Site Investigator.
Piotr Janik, Medical University of Warsaw, Poland, Site Investigator.
Nicola Johns, Scottish Huntington's Association Whyteman's Brae Hospital Fife, UK, Site Staff.
Lesley Jones, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Investigator.
Una Jones, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Staff.
Caroline K. Jurgens, Leiden University Medical Centre, Netherlands, Site Staff.
Alain Kaelin, Neurologische Klinik und Poliklinik/Zentrum für Bewegungsstörungen, Switzerland, Site Investigator.
Anna Kalbarczyk, Medical University of Warsaw, Poland, Site Staff.
Ann Kershaw, Cambridge Centre for Brain Repair, UK, Site Staff.
Hanan Khalil, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Staff.
Janina Kieni, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Aneta Klimberg, Medical University of Poznan, Poland, Site Staff.
Susana P. Koivisto, Oslo University Hospital (Rikshospitalet)
Kerstin Koppers, France, Language coordinator.
Christoph Michael Kosinski, Universitätsklinikum Aachen Neurologische Klinik, Germany, Site Staff.
Malgorzata Krawczyk, Krakowska Akademia Neurologii, Poland, Site Investigator.
Berry Kremer, Universitair Medisch Centrum St. Radboud Nijmegen, Netherlands, Site Investigator.
Wioletta Krysa, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Site Staff.
Hubert Kwiecinski, Medical University of Warsaw, Poland, Site Investigator.
Nayana Lahiri, The National Hospital for Neurology and Neurosurgery, London, UK, Site Staff.
Johann Lambeck, Universitätsklinik Freiburg, Germany, Site Staff.
Herwig Lange, Reha Zentrum in Dinslaken im Gesundheitszentrums Lang Dinslaken and Universitätsklinikum Münster, Germany, Site Investigator.
Fiona Laver, Gloucestershire Royal Hospital, UK, Site Staff.
K.L. Leenders, Polikliniek Neurologie Groningen, Netherlands, Site Staff
Jamie Levey, EHDN Central Coordination, France, Steering Committee.
Gabriele Leythaeuser, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Franziska Lezius, Universitätsklinikum Ulm, Germany, Site Staff.
Joan Roig Llesoy, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Matthias Löhle, Reha Zentrum in Dinslaken im Gesundheitszentrums Lang Dinslaken, Germany, Site Staff.
Cristobal Diez-Aja López, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Fortuna Lorenza, Hospital Universitario Virgen de la Arrixaca Murcia, Spain, Site Staff.
Giovanna Loria, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Staff.
Markus Magnet, LKH Graz Abteilung für Psychiatrie, Austria, Site Staff.
Paola Mandich, Università di Genova, Italy, Site Investigator.
Roberta Marchese, Università di Genova, Italy, Site Investigator.
Jerzy Marcinkowski, Medical University of Poznan, Poland, Site Investigator.
Caterina Mariotti, Fondazione IRCCS Istituto Neurologico Carlo Besta Milan, Italy, Site Staff.
Natividad Mariscal, Hospital General Yagüe Burgos Granada, Spain, Site Staff.
Ivana Markova, Castle Hill Hospital Hull, UK, Site Staff.
Ralf Marquard, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Kirsti Martikainen, Rehabilitation Centre Suvituuli Turku-Suvituuli, Finland, Site Investigator.
Isabel Haro Martínez, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Asuncion Martínez-Descals, Madrid-Fundación Jiménez Díaz, Spain, Site Staff.
T. Martino, Neurogenetics and Rare Disease Centre Pozzilli, Italy, Site Staff
Sarah Mason, Cambridge Centre for Brain Repair, UK, Site Staff.
Sue McKenzie, Scottish Huntington's Association Whyteman's Brae Hospital Fife, UK, Site Investigator.
Claudia Mechi, Universita' degli Studi di Firenze /Azienda Ospedaliera, Italy, Site Staff.
Tiago Mendes, Hospital de Santa Maria/Instituto de Medicina Molecular Lisbon, Portugal, Site Staff.
Tiago Mestre, Hospital de Santa Maria/Instituto de Medicina Molecular Lisbon, Portugal, Language coordinator.
Julia Middleton, Leicestershire Partnership Trust Mill Lodge, UK, Site Staff.
Eva Milkereit, Universitätsklinikum Aachen Neurologische Klinik, Germany, Site Staff.
Joanne Miller, Abercromby Center Glasgow, UK, Site Staff.
Julie Miller, Castle Hill Hospital Hull, UK, Site Staff.
Sara Minster, The Institute of Medical Genetics/University Hospital of Wales, UK, Language coordinator.
Jens Carsten Möller, Universität Marburg, Germany, Site Investigator.
Daniela Monza, Fondazione IRCCS Istituto Neurologico Carlo Besta Milan, Italy, Language coordinator.
Blas Morales, Hospital General Yagüe Burgos Granada, Spain, Site Investigator.
Laura V. Moreau, Hospital Universitario Virgen de la Arrixaca Murcia, Spain, Site Staff
Jose L. López-Sendón Moreno, Hospital Ramón y Cajal Madrid, Spain, Site Staff.
Alexander Münchau, Universitätsklinikum Hamburg-Eppendorf/Klinik und Poliklinik für, Germany, Site Investigator.
Ann Murch, Leicestershire Partnership Trust Mill Lodge, UK, Site Staff.
Jørgen E. Nielsen, Hukommelsesklinikken Rigshospitalet Panum Instituttet Copenhagen, Denmark, Steering Committee and Site Investigator.
Anke Niess, Universitätsklinikum Ulm, Germany, Site Staff.
Anne Nørremølle, Hukommelsesklinikken Rigshospitalet Panum Instituttet Copenhagen, Denmark, Site Investigator.
Marianne Novak, The National Hospital for Neurology and Neurosurgery, London, UK, Site Staff.
Kristy O'Donovan, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Staff.
Michael Orth, Universitätsklinikum Hamburg-Eppendorf/Klinik und Poliklinik für, Germany, Language coordinator.
Daniela Otti, LKH Graz Abteilung für Psychiatrie, Austria, Site Staff.
Michael Owen, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Investigator.
Helene Padieu, Centre de référence maladie de Huntington, Groupe Hospitalier Chenevier-Mondor, Créteil, France, Language coordinator.
Marco Paganini, Universita' degli Studi di Firenze /Azienda Ospedaliera, Italy, Site Staff.
Annamaria Painold, LKH Graz Abteilung für Psychiatrie, Austria, Site Staff.
Markku Päivärinta, Finnish Parkinson Association, Finland, Steering Committee.
Lucy Partington-Jones, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Staff.
Laurent Paterski, France, Language coordinator.
Nicole Paterson, Cambridge Centre for Brain Repair, UK, Site Staff.
Dawn Patino, Leicestershire Partnership Trust Mill Lodge, UK, Site Staff.
Michael Patton, Leicestershire Partnership Trust Mill Lodge, UK, Site Staff.
Alexander Peinemann, Klinikum rechts der Isar der Neurologischen Klinik und Poliklinik der Technischen Universität München, Germany, Site Staff.
Nadia Peppa, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Language coordinator.
Maria Fuensanta Noguera Perea, Hospital Universitario Virgen de la Arrixaca Murcia, Spain, Site Investigator.
Maria Peterson, St. Georges-Hospital London, UK, Site Staff.
Silvia Piacentini, Universita' degli Studi di Firenze /Azienda Ospedaliera, Italy, Site Investigator.
Carla Piano, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Staff.
Regina Pons i Càrdenas, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Christian Prehn, Huntington-Zentrum (NRW).
Kathleen Price, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Staff.
Daniela Probst, Universitätsklinikum Aachen Neurologische Klinik, Germany, Site Staff.
Oliver Quarrell, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Investigator.
Purificacion Pin Quiroga, Hospital Clínico Universitario San Carlos Madrid-Clinico, Spain, Site Staff.
Tina Raab, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Maryla Rakowicz, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Site Investigator.
Ashok Raman, Castle Hill Hospital Hull, UK, Site Staff.
Lucy Raymond, Cambridge Centre for Brain Repair, UK, Site Investigator.
Ralf Reilmann, Universitätsklinikum Münster, Germany, Site Investigator.
Gema Reinante, Hospital Universitario Virgen de la Arrixaca Murcia, Spain, Site Staff.
Karin Reisinger, LKH Graz Abteilung für Psychiatrie, Austria, Site Staff.
Lars Retterstol, Oslo University Hospital (Ulleval).
Pascale Ribaï, Institut de Pathologie et de Génétique Charleroi, Belgium, Site Investigator.
Antonio V. Riballo, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff
Guillermo G. Ribas, Hospital Ramón y Cajal Madrid, Spain, Site Staff
Sven Richter, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Hugh Rickards, The Barberry Centre Birmingham, UK, Site Investigator.
Carlo Rinaldi, Azienda Ospedaliera Universitaria Federico II Naples, Italy, Site Staff.
Ida Rissling, Universität Marburg, Germany, Site Staff.
Stuart Ritchie, Abercromby Center Glasgow, UK, Site Investigator.
Susana Vázquez Rivera, Hospital Clínico Universitario San Carlos Madrid-Clinico, Spain, Site Staff.
Misericordia Floriach Robert, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Elvira Roca, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Silvia Romano, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Staff.
Anna Maria Romoli, Universita' degli Studi di Firenze /Azienda Ospedaliera, Italy, Site Staff.
Raymond A.C. Roos, Leiden University Medical Centre, Netherlands, Steering Committee and Site Investigator.
Niini Røren, formerly Heinonen.
Sarah Rose, St. Georges-Hospital London, UK, Site Staff.
Elisabeth Rosser, The National Hospital for Neurology and Neurosurgery, London, UK, Site Investigator.
Anne Rosser, The Institute of Medical Genetics/University Hospital of Wales, UK, Site Investigator.
Fabiana Rossi, Azienda Ospedaliera Universitaria Federico II Naples, Italy, Site Staff.
Jean Rothery, Scottish Huntington's Association Whyteman's Brae Hospital Fife, UK, Site Staff.
Monika Rudzinska, Krakowska Akademia Neurologii, Poland, Site Investigator.
Pedro J. García Ruíz, Madrid-Fundación Jiménez Díaz, Spain, Site Investigator.
Belan Garzon Ruíz, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Cinzia Valeria Russo, Azienda Ospedaliera Universitaria Federico II Naples, Italy, Site Staff.
Danuta Ryglewicz, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Site Staff.
Carston Saft, Huntington-Zentrum (NRW).
Elena Salvatore, Azienda Ospedaliera Universitaria Federico II Naples, Italy, Site Staff.
Vicenta Sánchez, Madrid-Fundación Jiménez Díaz, Spain, Site Staff.
Sigrid Botne Sando, St. Olavs Hospital Trondheim, Norway, Site Investigator.
Pavla Šašinková, CzechRepublic, Language coordinator.
Christian Sass, Universitätsklinikum Aachen Neurologische Klinik, Germany, Site Staff.
Monika Scheibl, LKH Graz Abteilung für Psychiatrie, Austria, Site Staff.
Johannes Schiefer, Universitätsklinikum Aachen Neurologische Klinik, Germany, Site Investigator.
Christiane Schlangen, Universitätsklinikum Aachen Neurologische Klinik, Germany, Site Staff.
Simone Schmidt, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden/Klinik und Poliklinik für Neurologie Dresden, Germany, Site Staff.
Helmut Schöggl, LKH Graz Abteilung für Psychiatrie, Austria, Site Staff.
Caroline Schrenk, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Michael Schüpbach, Neurologische Klinik und Poliklinik/Zentrum für Bewegungsstörungen, Switzerland, Site Staff.
Michele Schuierer, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Ana Rojo Sebastián, Hospital Mútua de Terrassa Barcelona, Spain, Steering Committee and Site Investigator.
Amina Selimbegovic-Turkovic, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Justyna Sempolowicz, Medical University of Poznan, Poland, Site Staff.
Mark Silva, Gloucestershire Royal Hospital, UK, Site Investigator.
Emilia Sitek, St. Adalbert Hospital Gdansk; Medical University of Gdansk, Poland, Site Staff.
Jaroslaw Slawek, St. Adalbert Hospital Gdansk; Medical University of Gdansk, Poland, Site Investigator.
Julie Snowden, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Investigator.
Francesco Soleti, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Staff.
Paola Soliveri, Fondazione IRCCS Istituto Neurologico Carlo Besta Milan, Italy, Site Staff.
Andrea Sollom, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Staff.
Witold Soltan, St. Adalbert Hospital Gdansk; Medical University of Gdansk, Poland, Site Investigator.
Sandro Sorbi, Universita' degli Studi di Firenze /Azienda Ospedaliera, Italy, Site Investigator.
Sven Asger Sorensen, Hukommelsesklinikken Rigshospitalet Panum Instituttet Copenhagen, Denmark, Site Staff.
Maria Spadaro, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Staff.
Michael Städtler, Klinikum rechts der Isar der Neurologischen Klinik und Poliklinik der Technischen Universität München, Germany, Site Staff.
Christiane Stamm, Huntington-Zentrum (NRW).
Tanja Steiner, Huntington-Zentrum (NRW).
Jette Stokholm, Hukommelsesklinikken Rigshospitalet Panum Instituttet Copenhagen, Denmark, Site Staff.
Bodil Stokke, Oslo University Hospital (Ulleval).
Cheryl Stopford, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Staff.
Alexander Storch, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden/Klinik und Poliklinik für Neurologie Dresden, Germany, Site Investigator.
Katrin Straßburger, Huntington-Zentrum (NRW).
Lars Stubbe, Universitätsklinikum Hamburg-Eppendorf/Klinik und Poliklinik für, Germany, Site Staff.
Anna Sulek, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Site Staff.
Andrzej Szczudlik, Krakowska Akademia Neurologii, Poland, Site Investigator.
Sarah Tabrizi, The National Hospital for Neurology and Neurosurgery, London, UK, Steering Committee and Site Investigator.
Rachel Taylor, The National Hospital for Neurology and Neurosurgery, London, UK, Site Coordinator.
Santiago Duran-Sindreu Terol, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Gareth Thomas, Scottish Huntington's Association Whyteman's Brae Hospital Fife, UK, Site Investigator.
Jennifer Thompson, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Investigator.
Aileen Thomson, Gloucestershire Royal Hospital, UK, Site Investigator.
Katherine Tidswell, The Royal Hallamshire Hospital/Sheffield Children's Hospital, UK, Site Staff.
Maria M. Antequera Torres, Hospital Universitario Virgen de la Arrixaca Murcia, Spain, Site Staff.
Jean Toscano, Chapel Allerton Hospital Leeds, UK, Site Staff.
Jenny Townhill, formerly Naji.
Sonja Trautmann, Universitätsklinikum Ulm, Germany, Site Coordinator.
Tecla Tucci, Azienda Ospedaliera Universitaria Federico II Naples, Italy, Site Staff.
Katri Tuuha, Rehabilitation Centre Suvituuli Turku-Suvituuli, Finland, Site Staff.
Tereza Uhrova, Institute of Biology and Medical Genetics, First Faculty of Medicine, Charles University in Prague and General University Hospital in Prague, Czech Republic, Steering Committee.
Anabela Valadas, Hospital de Santa Maria/Instituto de Medicina Molecular Lisbon, Portugal, Site Staff.
Monique S.E. van Hout, Medisch Spectrum Twente Enschede, Netherlands, Site Staff
J.C.H. van Oostrom, Polikliniek Neurologie Groningen, Netherlands, Site Staff
Jeroen P.P. van Vugt, Medisch Spectrum Twente Enschede, Netherlands, Site Investigator.
Walsem Marleen R. vanm, Oslo University Hospital (Rikshospitalet).
Wim Vandenberghe, Department of Neurology, University Hospital Leuven, Belgium, Steering Committee.
Christine Verellen-Dumoulin, Institut de Pathologie et de Génétique Charleroi, Belgium, Steering Committee and Site Investigator.
Mar Ruiz Vergara, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
C.C.P. Verstappen, Universitair Medisch Centrum St. Radboud Nijmegen, Netherlands, Site Investigator.
Nichola Verstraelen, formerly Ritchie.
Celia Mareca Viladrich, Hospital Mare de Deu de La Merced Barcelona, Spain, Site Staff.
Clara Villanueva, Hospital Clínico Universitario San Carlos Madrid-Clinico, Spain, Site Staff.
Jan Wahlström, Sahlgrenska University Hospital, Gothenburg, Sweden, Steering Committee.
Thomas Warner, The National Hospital for Neurology and Neurosurgery, London, UK, Site Investigator.
Raghild Wehus, Oslo University Hospital (Rikshospitalet).
Adolf Weindl, Klinikum rechts der Isar der Neurologischen Klinik und Poliklinik der Technischen Universität München, Germany, Site Investigator.
Cornelius J. Werner, Universitätsklinikum Aachen Neurologische Klinik, Germany, Site Staff.
Leann Westmoreland, Centre and Central Manchester University Hospitals NHS Foundation Trust University of Manchester/Manchester Academic Health Sciences, UK, Site Staff.
Patrick Weydt, Universitätsklinikum Ulm, Germany, Site Investigator.
Alexandra Wiedemann, Isar-Amper-Klinikum Taufkirchen, Germany, Site Staff.
Edward Wild, The National Hospital for Neurology and Neurosurgery, London, UK, Site Staff.
Sue Wild, Chapel Allerton Hospital Leeds, UK, Site Staff.
Marie-Noelle Witjes-Ané, Leiden University Medical Centre, Netherlands, Language coordinator.
Grzegorz Witkowski, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Site Investigator.
Magdalena Wójcik, Krakowska Akademia Neurologii, Poland, Site Investigator.
Martin Wolz, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden/Klinik und Poliklinik für Neurologie Dresden, Germany, Site Investigator.
Annett Wolz, Universitätsklinikum Carl Gustav Carus an der Technischen Universität Dresden/Klinik und Poliklinik für Neurologie Dresden, Germany, Site Staff.
Jan Wright, The Barberry Centre Birmingham, UK, Site Staff.
Pam Yardumian, Chapel Allerton Hospital Leeds, UK, Site Staff.
Shona Yates, Scottish Huntington's Association Whyteman's Brae Hospital Fife, UK, Site Staff.
Elizaveta Yudina, formerly Tarasova.
Jacek Zaremba, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Steering Committee and Site Investigator.
Sabine W. Zaugg, Neurologische Klinik und Poliklinik/Zentrum für Bewegungsstörungen, Switzerland, Site Staff
Elzbieta Zdzienicka, Institute of Psychiatry and Neurology Warsaw-IPiN, Poland, Site Investigator.
Daniel Zielonka, Medical University of Poznan, Poland, Language coordinator.
Euginiusz Zielonka, Medical University of Poznan, Poland, Language coordinator.
Paola Zinzi, Istituto di Neurobiologia e Medicina Molecolare & Istituto di Scienze e Tecnologie della Cognizione /CNR Istituto di Neurologia Università Cattolica Roma, Italy, Site Investigator and Language coordinator.
Simone Zittel, Universitätsklinikum Hamburg-Eppendorf/Klinik und Poliklinik für, Germany, Site Staff.
Birgrit Zucker, Universitätsklinik Freiburg, Germany, Site Investigator.
John Adams, Centre for Addiction and Mental Health, Toronto, Canada, Site Investigator.
Pinky Agarwal, Booth Gardner Parkinson's Care Center, Kirkland, WA, USA, Site Investigator.
Irina Antonijevic, CHDI Foundation, Inc., USA, Steering Committee and Science Committee.
Christopher Beck, University of Rochester, USA, Publications & Data Use Committee and Biostatistics/Coordination Center.
Edmond Chiu, The University of Melbourne, Australia, Site Investigator.
Andrew Churchyard, St Vincent's Aged Mental Health Service, Australia, Site Investigator.
Amy Colcher, University of Pennsylvania, USA, Site Investigator.
Jody Corey-Bloom, University of California, San Diego, USA, Site Investigator.
Ray Dorsey, Johns Hopkins University, USA, Publications & Data Use Committee (Co-Chair).
Carolyn Drazinic, University of Connecticut, USA, Site Investigator.
Richard Dubinsky, University of Kansas Medical Center, USA, Site Investigator.
Kevin Duff, University of Utah, USA, Site Investigator.
Stewart Factor, Emory University School of Medicine, Georgia, USA, Site Investigator.
Tatiana Foroud, Indiana University School of Medicine, USA, Steering Committee (Co-PI).
Sarah Furtado, University of Calgary, Canada, Site Investigator.
Joe Giuliano, CHDI Foundation, Inc., USA, Publications & Data Use Committee.
Timothy Greenamyre, University of Pittsburgh, USA, Site Investigator.
Don Higgins, Albany Medical College, USA, Site Investigator.
Joseph Jankovic, Baylor College of Medicine, Texas, USA, Site Investigator.
Dana Jennings, Institute for Neurogenerative Disorders, Connecticut, USA, Site Investigator.
Un Jung Kang, University of Chicago, USA, Site Investigator.
Sandra Kostyk, Ohio State University, USA, Site Investigator.
Rajeev Kumar, Colorado Neurological Institute, USA, Site Investigator.
Blair Leavitt, University of British Columbia, Canada, Site Investigator.
Mark LeDoux, University of Tennessee Health Science Center, USA, Site Investigator.
William Mallonee, Hereditary Neurological Disease Center, Kansas, USA, Site Investigator.
Frederick Marshall, University of Rochester, USA, Site Investigator.
Eric Mohlo, Albany Medical College, USA, Site Investigator.
John Morgan, Medical College of Georgia, USA, Site Investigator.
David Oakes, University of Rochester, USA, Publications & Data Use Committee and Biostatistics/Coordination Center.
Peter Panegyres, Graylands, Selby-Lemnos & Special Care Health Services, Australia, Site Investigator.
Michel Panisset, Hôtel-Dieu, Hôpital-CHUM, Montreal, Canada, Site Investigator.
Susan Perlman, UCLA, USA, Site Investigator.
Joel Perlmutter, Washington University, USA, Site Investigator.
Kimberly Quaid, Indiana University School of Medicine, USA, Site Investigator.
Lynn Raymond, University of British Columbia, Canada, Site Investigator.
Fredy Revilla, University of Cincinnati/Cincinnati Children's Hospital, USA, Site Investigator.
Suzanne Robertson, University of Rochester, USA, Biostatistics/Coordination Center.
Bradley Robottom, University of Maryland School of Medicine, USA, Site Investigator.
Juan Sanchez-Ramos, University of South Florida, USA, Site Investigator.
Burton Scott, Duke University Medical Center, USA, Site Investigator.
Kathleen Shannon, Rush University Medical Center, USA, Site Investigator.
Ira Shoulson, University of Rochester NY, USA, Steering Committee (PI).
Carlos Singer, University of Miami, USA, Site Investigator.
Samer Tabbal, Washington University, USA, Site Investigator.
Claudia Testa, Emory University School of Medicine, Georgia, USA, Site Investigator.
Kammen Dan van, CHDI Foundation, Inc., USA, Steering Committee.
Louise Vetter, Huntington's Disease Society of America, USA, Publications & Data Use Committee.
Francis Walker, Wake Forest University School of Medicine, USA, Site Investigator.
John Warner, CHDI Foundation, Inc., USA, Publications & Data Use Committee.
illiam Weiner, University of Maryland School of Medicine, USA, Site Investigator.
Vicki Wheelock, University of California, Davis, USA, Site Investigator.
Olga Yastrubetskaya, The University of Melbourne, Australia, Site Investigator.
Stacey Barton, Washington University, USA, Site Staff.
Janice Broyles, University of Kansas Medical Center, USA, Site Staff.
Ronda Clouse, Columbia University Medical Center, USA, Site Staff.
Allison Coleman, University of British Columbia, Canada, Site Staff.
Robert Davis, University of Virginia, USA, Site Staff.
Joji Decolongon, University of British Columbia, Canada, Site Staff.
Jeanene DeLaRosa, University of Texas, USA, Site Staff.
Lisa Deuel, University of Rochester, USA, Biostatistics/Coordination Center.
Susan Dietrich, University of Virginia, USA, Site Staff.
Hilary Dubinsky, University of Kansas Medical Center, USA, Site Staff.
Ken Eaton, University of Rochester, USA, Biostatistics/Coordination Center.
Diane Erickson, Colorado Neurological Institute, USA, Site Staff.
Mary Jane Fitzpatrick, University of Connecticut, USA, Site Staff.
Steven Frucht, Columbia University Medical Center, USA, Site Staff.
Maureen Gartner, University of Cincinnati/Cincinnati Children's Hospital, USA, Site Staff.
Jody Goldstein, University of California San Diego, USA, Site Staff.
Jane Griffith, Westmead Hospital, Australia, Site Staff.
Charlyne Hickey, University of Rochester, USA, Site Staff.
Victoria Hunt, Wake Forest University School of Medicine, USA, Site Staff.
Jeana Jaglin, Rush University Medical Center, USA, Site Staff.
Mary Lou Klimek, University of Calgary, Canada, Site Staff.
Pat Lindsay, University of Rochester, USA, Biostatistics/Coordination Center.
Elan Louis, Columbia University Medical Center, USA, Site Staff.
Clemet Loy, Westmead Hospital, Australia, Site Staff.
Nancy Lucarelli, University of Pittsburgh, USA, Site Staff.
Keith Malarick, Massachusetts General Hospital, USA, Site Staff.
Amanda Martin, University of California Davis, USA, Site Staff.
Robert McInnis, Massachusetts General Hospital, USA, Site Staff.
Carol Moskowitz, Columbia University Medical Center, USA, Site Staff.
Lisa Muratori, Columbia University Medical Center, USA, Site Staff.
Frederick Nucifora, Johns Hopkins University, USA, Site Staff.
Christine O'Neill, Wake Forest University School of Medicine, USA, Site Staff.
Alicia Palao, Baylor College of Medicine Texas, USA, Site Staff.
Guerry Peavy, University of California San Diego, USA, Site Staff.
Monica Quesada, University of Miami, USA, Site Staff.
Amy Schmidt, Washington University, USA, Site Staff.
Vicki Segro, Colorado Neurological Institute, USA, Site Staff.
Elaine Sperin, Emory University School of Medicine, USA, Site Staff.
Greg Suter, Hereditary Neurological Disease Centre Kansas, USA, Site Staff.
Kalo Tanev, Massachusetts General Hospital, USA, Site Staff.
Teresa Tempkin, University of California Davis, USA, Site Staff.
Curtis Thiede, University of California Los Angeles CA, USA, Site Staff.
Paula Wasserman, Columbia University Medical Center, USA, Site Staff.
Claire Welsh, Johns Hopkins University, USA, Site Staff.
Melissa Wesson, Indiana University School of Medicine, USA, Site Staff.
Elizabeth Zauber, Indiana University School of Medicine, USA, Site Staff.
AUTHOR AFFILIATIONS
From the Center for Human Genetic Research (J.-M.L., J.-H.L., T.G., J.S.M., D.L., M.E.M., J.F.G.), Massachusetts General Hospital, Boston; UnIGENe, IBMC–Institute for Molecular and Cellular Biology (E.M.R.), and Instituto de Ciências Biomédicas Abel Salazar (J.S.), Universidade do Porto, Porto, Portugal; Center for Molecular Medicine and Therapeutics (M.R.H., S.C.W.), University of British Columbia, Vancouver, BC, Canada; Regional Medical Genetics Centre, Belfast HSC Trust, Belfast, and University of Ulster (P.M.), Coleraine, UK; Hennepin County Medical Center (M.N.), Minneapolis, MN; Department of Psychiatry and Behavioral Sciences (C.A.R., R.L.M.), Johns Hopkins University, Baltimore, MD; Neurogenetics Unit and Centre for Rare Diseases (F.S., S.O.), IRCCS Neuromed, Pozzilli, Italy; Istituto Nazionale Neurologico C. Besta (S.D.D.), Milan, Italy; Department of Neurology (E.G.-T.), and Department of Genetics (C.A.), Fundación Jiménez Diaz, Madrid, Spain; Department of Clinical Neurosciences (O.S.), University of Calgary, Calgary, AB, Canada; Sydney Medical School (R.J.A.T.), University of Sydney, and Department of Neurology (E.M.), Westmead Hospital, Sydney, NSW, Australia; Department of Biology (A.N.), University Tor Vergata, and Institute of Neurobiology and Molecular Medicine (M.F.), Rome, Italy; Center for Neurodegenerative Disease (R.J.), Emory University School of Medicine, Atlanta, GA; Department of Neurology (T.A.), University of Florida, Gainesville; Department of Neurology (S.F., M.H.S.-H., R.H.M.), Boston University School of Medicine, Boston, MA; MassGeneral Institute for Neurodegenerative Disease (S.M.H., H.D.R.), Massachusetts General Hospital, Charlestown; Department of Neurology (M.B.H.), University of Virginia, Charlottesville; Memory and Aging Center (A.Z.), University of California, San Francisco; Department of Neuropsychiatry and Behavioral Science (R.K.A.), University of South Carolina School of Medicine, Columbia; Department of Neurology (K.M.), Columbia University Medical Center, New York, NY; Departments of Psychiatry and Neurology (J.S.P.), The University of Iowa Roy and Lucille Carver College of Medicine, Iowa City; Department of Neurology (G.B.L.), Ulm University, Ulm, Germany.
AUTHOR CONTRIBUTIONS
Dr. J.-M. Lee conceived of and performed the statistical analysis and interpretation and drafted the manuscript. Drs. Ramos, J.-H. Lee, Gillis, and Mysore generated and interpreted molecular data. Drs. Hayden, Warby, Morrison, Nance. Ross, Margolis, Squitieri, Orobello, Di Donato, Gomez-Tortosa, Ayuso, Suchowersky, Trent, McCusker, Novelletto, Frontali, Jones, Ashizawa, Frank, Saint-Hilaire, Hersch, Rosas, Lucente, Harrison, Zanko, Abramson, Marder, and Sequeiros aided in the conceptualization and design of the study and revised the manuscript for intellectual content. Drs. Paulsen and Landwehrmeyer revised the manuscript for intellectual content. Drs. Myers, MacDonald, and Gusella participated in conceptualization and design of the study and interpretation of the data and revised the manuscript for intellectual content.
STUDY FUNDING
Supported by grants from the National Institute of Neurological Disorders and Stroke (NINDS) (“Huntington's Disease Center Without Walls”; NS016367), the CHDI Foundation, Inc., and the Huntington's Disease Society of America's Coalition for the Cure. J.H.L. received a fellowship from the National Research Foundation of Korea and E.M.R. received a scholarship from the Fundação para a Ciência e a Tecnologia of Portugal (FCT). PREDICT-HD is supported by NINDS grant NS040068. Both PREDICT-HD and COHORT are also supported by the CHDI Foundation, Inc. and REGISTRY is supported by the High Q Foundation.
DISCLOSURE
Dr. J-M. Lee reports no disclosures. Dr. Ramos received a scholarship from FCT (SFRH/BD/44335/2008). Dr. J.-H. Lee received support from the National Research Foundation of Korea (NRF-2009–352-E0010). Dr. Gillis and Dr. Mysore report no disclosures. Dr. Hayden serves as Editor-in-Chief of Clinical Genetics. Dr. Warby reports no disclosures. Dr. Morrison is a section editor of The Oncologist. Dr. Nance received honoraria from the Huntington's Disease Society of America HD Training Course for Physicians, the American Academy of Neurology Genetics in Neurology lecture and lectures at Augsburg College, royalties from Oxford University Press for Juvenile Huntington's Disease 2009, reimbursement for NIH Study Section service and the Parkinson Study Group Scientific Review Board, Center of Excellence support from the Huntington Disease Society of America and the National Parkinson Foundation, and grant support from Santhera Pharmaceuticals, NeuroSearch, Medivation/Pfizer, Schwarz Biosciences, IMPAX Pharmaceuticals, Neuraltus Pharmaceuticals and Teva Pharmaceuticals, National Institutes of Health NINDS grants NS044466, NS036630, NS040068, NS052592, and NS060118, NCCAM grant AT000613 and NHGRI grant HG02449, and grants from the CHDI Foundation (HP Therapeutics), the High Q Foundation, and the Michael J. Fox Foundation/Northwestern Dixon Foundation, and declares spousal participation in Speaker's bureaus: Roche, Sanford. Dr. Ross received research funding from National Institutes of Health NINDS grants NS16375, NS055252, NS060118, and NS069422. Dr. Margolis received research funding from National Institutes of Health NINDS grant NS016375, Medivation/Pfizer, CHDI Foundation Inc., and Forest Laboratories and was a consultant to AstraZeneca. Dr. Squitieri and Dr. Orobello report no disclosures. Dr. Di Donato was on the Scientific Advisory Board of the Fondazione Mariani Onlus, Milan, Italy, and a consultant Advisor for Preclinical Research and International Relationships of the Scientific Direction of the Fondazione IRCSS Instituto Neurologico Carlo Besta, Milan, Italy, and received support from the Ministero della Salute, Italy, and from the Fondazione Cariplo, Milan, Italy. Dr. Gomez-Tortosa reports no disclosures. Dr. Ayuso has received research support from CIBERER, ISCIII, Madrid, Spain. Dr. Suchowersky was an Advisory Board Member for Allergan, Biovail and Novartis, on the editorial boards of the Canadian Journal of Neurological Sciences and Nature Reviews Neurology, and received support from Abbott Laboratories, from National Institutes of Health NINDS grant NS044431, and from the CHDI Foundation, Inc. Dr. Trent reports royalties for the book Molecular Medicine, 3rd edition (Elsevier) and support from Australian Research Council LIED grants LE0989147 and LE100100130. Dr. McCusker is on the editorial board of Tremor and Hyperkinetic Movements. Dr. Novelletto reports no disclosures. Dr. Frontali received support from Italian Drug Agency (AIFA) grant FARM659PTX. Dr. Jones received support from the National Institutes of Health NINDS grants NS040068 and NS060118 and from the High Q Foundation and the Huntington's Disease Society of America. Dr. Ashizawa received support from the National Institutes of Health NINDS grant NS068897. Dr. Frank consulted for and received support from Lundbeck Pharmaceuticals. Dr. Saint-Hilaire was on the Steering Committee of the Safinamide (MOTION) study of EMD Serono, lectured at the meetings of the Movement Disorder Society and the American Academy of Neurology, is a member of the speaker's bureau of Teva Pharmaceuticals, and received support from Bayer, EMD Serono, and Teva Pharmaceuticals, National Institutes of Health NINDS grant NS050095, and NHGRI grant HG02449, and from the Michael J. Fox Foundation. Dr. Hersch was a consultant to Link Medicine and Alnylam Pharmaceuticals and received support from the National Institutes of Health NCCAM grant AT000613, NINDS grant NS071789, and from the Huntington's Disease Society of America. Dr. Rosas and Dr. Lucente report no disclosures. Dr. Harrison received support from National Institutes of Health NCCAM grant AT000613, from the CHDI Foundation, Inc., and from the Huntington's Disease Society of America. Dr. Zanko reports no disclosures. Dr. Abramson received support from National Institutes of Health NICHD grant HD062550, South Carolina Council on Disabilities grant 18120 FL00, and a grant from the Fullerton Foundation. Dr. Marder served on the editorial board of Neurology® and as an editor of Current Neurology and Neuroscience and received support from Amarin Corporation, NeuroSearch Sweden AB, and Medivation, and from National Institutes of Health NINDS grant NS036630, NCRR grant RR024156, and PO412196-G from NHGRI grant HG02449 at the University of Rochester as well as from the Parkinson Disease Foundation, the Huntington's Disease Society of America, the Parkinson Study Group, the Michael J. Fox Foundation, and the CHDI Foundation, Inc. Dr. Sequeiros was a compensated speaker for the Fundacion Jimenez Diaz, served on the editorial boards of Clinical Genetics, the Journal of Community Genetics, and the Journal of Biomedicine and Biotechnology, and received research support from the FCT “Financiamento Plurianual de Unidades de investigação” and from the European Commission FP6 Network of Excellence EuroGentest: Genetics Testing in Europe. Dr. Paulsen received funding from National Institutes of Health NINDS grant NS040068 and from the CHDI Foundation, Inc. Dr. Landwehrmeyer received a speaker honorarium/reimbursement from DGNP-Temmler Pharma, royalties from Neurologie Compact (Verlag) and Juvenile HD (Oxford Press), consulting support from the CHDI Foundation, Inc., clinical trial support from Medivation and Neurosearch, and support from the European Union (FP7 Paddington) and the High Q Foundation/CHDI Foundation. Dr. Myers received funding from National Institutes of Health NINDS grant NS016367 and from the Jerry MacDonald Huntington Research Fund. Dr. MacDonald serves as an Associate Editor of PLoS Genetics, is on the Board of Directors of the Huntington's Disease Society of America, and received support from National Institutes of Health NINDS grants NS016367, NS032765, and NS033648 and from the Huntington's Disease Society of America and the CHDI Foundation, Inc. Dr. Gusella is on the Scientific Advisory Board of Quest Diagnostics, Inc., is on the editorial boards of DNA and Cell Biology, Neurobiology of Disease, Neurogenetics, Biomed Central Neuroscience, Biomed Central Biology, and Molecular Autism, and received support from National Institutes of Health NINDS grants NS016367, NS024279, and NS069422, NIGMS grant GM061354, and NICHD grant HD06528 and from the Simons Foundation Autism Research Initiative, Autism Speaks, CHDI Foundation, Inc., and the Huntington's Disease Society of America.
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