Funding for this research was provided by:
Multiple System Atrophy Coalition (2017-10-007)
California Department of Public Health (18-10926)
Michael J. Fox Foundation for Parkinson's Research (17990, 18303)
National Ataxia Foundation (20201551)
Cure Sanfilippo Foundation (20215318)
Received: 18 December 2022
Accepted: 3 March 2023
First Online: 20 March 2023
: Blood-collection procedures were approved by the respective Human Subjects Committees at UCLA, New York University, Columbia University, and University of North Carolina Chapel Hill and informed consent was obtained from all participants.
: Not applicable.
: The authors declare that they have no competing interests.