About the Authors

Taye H. Hamza

Affiliation New York State Department of Health Wadsworth Center, Albany, New York, United States of America

Honglei Chen

Affiliation Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, United States of America

Erin M. Hill-Burns

Affiliation New York State Department of Health Wadsworth Center, Albany, New York, United States of America

Shannon L. Rhodes

Affiliation Department of Epidemiology, School of Public Health, University of California Los Angeles, Los Angeles, California, United States of America

Jennifer Montimurro

Affiliation New York State Department of Health Wadsworth Center, Albany, New York, United States of America

Denise M. Kay

Affiliation New York State Department of Health Wadsworth Center, Albany, New York, United States of America

Albert Tenesa

Affiliation Institute of Genetics and Molecular Medicine and The Roslin Institute, University of Edinburgh, Edinburgh, United Kingdom

Victoria I. Kusel

Affiliation New York State Department of Health Wadsworth Center, Albany, New York, United States of America

Patricia Sheehan

Affiliation New York State Department of Health Wadsworth Center, Albany, New York, United States of America

Muthukrishnan Eaaswarkhanth

Affiliation New York State Department of Health Wadsworth Center, Albany, New York, United States of America

Dora Yearout

Affiliations New York State Department of Health Wadsworth Center, Albany, New York, United States of America, VA Puget Sound Health Care System and Department of Neurology, University of Washington, Seattle, Washington, United States of America

Ali Samii

Affiliation VA Puget Sound Health Care System and Department of Neurology, University of Washington, Seattle, Washington, United States of America

John W. Roberts

Affiliation Virginia Mason Medical Center, Seattle, Washington, United States of America

Pinky Agarwal

Affiliation Booth Gardner Parkinson's Care Center, Evergreen Hospital Medical Center, Kirkland, Washington, United States of America

Yvette Bordelon

Affiliation Department of Neurology, School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America

Yikyung Park

Affiliation Nutritional Epidemiology Branch, Divisions of Cancer Epidemiology and Genetics, National Cancer Institute, Bethesda, Maryland, United States of America

Liyong Wang

Affiliation Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, United States of America

Jianjun Gao

Affiliation Epidemiology Branch, National Institute of Environmental Health Sciences, Research Triangle Park, North Carolina, United States of America

Jeffery M. Vance

Affiliation Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, United States of America

Kenneth S. Kendler

Affiliation Virginia Institute for Psychiatric and Behavioral Genetics, Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia, United States of America

Silviu-Alin Bacanu

Affiliation Virginia Institute for Psychiatric and Behavioral Genetics, Department of Psychiatry, Virginia Commonwealth University, Richmond, Virginia, United States of America

William K. Scott

Affiliation Dr. John T. Macdonald Foundation Department of Human Genetics and John P. Hussman Institute for Human Genomics, University of Miami Miller School of Medicine, Miami, Florida, United States of America

Beate Ritz

Affiliations Department of Epidemiology, School of Public Health, University of California Los Angeles, Los Angeles, California, United States of America, Department of Neurology, School of Medicine, University of California Los Angeles, Los Angeles, California, United States of America, Department of Environmental Health Sciences, Center for Occupational and Environmental Health, School of Public Health, University of California Los Angeles, Los Angeles, California, United States of America

John Nutt

Affiliation Department of Neurology, Oregon Health and Sciences University, Portland, Oregon, United States of America

Stewart A. Factor

Affiliation Department of Neurology, Emory University School of Medicine, Atlanta, Georgia, United States of America

Cyrus P. Zabetian

Affiliation VA Puget Sound Health Care System and Department of Neurology, University of Washington, Seattle, Washington, United States of America

Haydeh Payami

hpayami@wadsworth.org

Affiliation New York State Department of Health Wadsworth Center, Albany, New York, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: HP. Performed the experiments: HP THH EMH-B. Analyzed the data: HP THH EMH-B PS ME. Contributed reagents/materials/analysis tools: HP SAF JN CPZ PA AS JWR HC SLR YB YP WKS LW JG JMV BR. Wrote the paper: HP. DNA and phenotype preparations and database operations: JM DY DMK VIK. Consulted on choice of analytical method: AT KSK S-AB.