2.1.2. Standard protocol approvals, registrations, and patient consents

All studies were approved by each respective Institutional Ethics Review Committee and all participants provided written informed consent. All studies were carried out in accordance with the Declaration of Helsinki.

Research ethics approval for the Tracking Parkinson’s study was provided by West of Scotland Research Ethics Service (reference 11/AL/0163). The study is registered with ClinicalTrials.gov under the identifier {"type":"clinical-trial","attrs":{"text":"NCT02881099","term_id":"NCT02881099"}}NCT02881099. Research ethics approval for the Parkinson’s Families Project was provided by the London Camden and King’s Cross ethics committee (reference 15/LO/0097) and the Health Research Authority. The study is registered with ClinicalTrials.gov under the identifier {"type":"clinical-trial","attrs":{"text":"NCT02760108","term_id":"NCT02760108"}}NCT02760108. The local Research Ethics Board number for samples processed at McGill University is IRB00010120, and the approved project identifier is 2017-2944, valid until December 2019, to be renewed then. The local Institutional Review Board approval for samples from Columbia University is AAAF3108. Ethical approval from 2 of the studies is published (Fernandez-Santiago et al., 2018; Trinh et al., 2016).