Author information:
(1)University of Washington, Department of Environmental and Occupational Health 
Sciences, Seattle, WA, USA. Electronic address: jlundin2@uw.edu.
(2)University of California San Diego, Department of Family and Preventive 
Medicine, La Jolla, CA, USA. Electronic address: hcheckoway@ucsd.edu.
(3)Washington University School of Medicine, Department of Neurology, St. Louis, 
MO, USA; American Parkinson Disease Association Advanced Center for Parkinson 
Research, St. Louis, MO, USA. Electronic address: criswells@neuro.wustl.edu.
(4)Washington University School of Medicine, Department of Neurology, St. Louis, 
MO, USA. Electronic address: hobsona@neuro.wustl.edu.
(5)Washington University School of Medicine, Department of Neurology, St. Louis, 
MO, USA. Electronic address: rachel.harris.621@gmail.com.
(6)Washington University School of Medicine, Department of Neurology, St. Louis, 
MO, USA; American Parkinson Disease Association Advanced Center for Parkinson 
Research, St. Louis, MO, USA. Electronic address: swisherl@neuro.wustl.edu.
(7)Washington University School of Medicine, Department of Internal Medicine, 
St. Louis, MO, USA. Electronic address: bevanoff@dom.wustl.edu.
(8)Washington University School of Medicine, Department of Neurology, St. Louis, 
MO, USA; American Parkinson Disease Association Advanced Center for Parkinson 
Research, St. Louis, MO, USA; University of the Witwatersrand, School of Public 
Health, Faculty of Health Sciences, Parktown, Johannesburg, South Africa. 
Electronic address: racetteb@neuro.wustl.edu.