The purpose of this study is to find a biomarker for Parkinson's disease (PD). A biomarker is an indicator of the presence of a disease, that can be measured, and that is able to give information about the progression, or severity, of it.~PD is a chronic neurological disease that progresses over time and causes a variety of symptoms, such as slowness of movement, stiffness and shaking. The symptoms of PD are caused by the malfunction and death of vital nerve cells in the brain. it is no known what causes PD and there is no biomarker for it.~Generally, PD occurs without a known cause, and is called sporadic PD. In a few cases, however, PD occurs because of a genetic mutation, and it is called genetic PD. Patients with genetic PD share features to sporadic PD patients. It is believed that studying people who carry mutations for genetic PD mutations would provide precious information on what are the causes of PD and help to devise successful treatments.~Participants will attend 4 visits in a 3 month period. These visits include an initial consent and assessment visit where some blood samples will also be taken. the second visit involves a PET scan with the tracer DASB along with an MRI scan. The third visit involves a SPECT scan. the fourth visit is optional and would be for a lumbar puncture visit. Each visit will last around 6 hours.
In this study, the investigators aim to find a biomarker of Parkinson's disease. This is done using imaging scans called Positron Emission tomography (PET), Single Photon Emission Computed Tomography (SPECT), and Magnetic Resonance Imaging (MRI). The findings will provide a deeper understanding of the brain changes in Parkinson's disease. More importantly, this study will help with the discovery and development of new medications aiming to delay progression of PD symptoms.