No objective measurement — or biomarker — currently exists to diagnose Parkinson’s disease (PD). Instead, doctors must rely on a person’s medical history and physical examination to recognize the disease. This can sometimes result in missed or incorrect diagnoses, so significant research efforts are underway to identify biomarker(s) and/or examination(s) that could diagnose PD more accurately.

One example of these research endeavors is an MJFF-funded study being conducted by Dr. David Munoz and colleagues at St. Michael’s Hospital in Toronto. They are measuring alpha-synuclein — the protein that clumps in brain cells of people with PD — in biopsies of the submandibular (salivary) gland, colon and skin of people with Parkinson’s. In doing so, the researchers hope to determine if any or all of these tests might provide a convenient route toward early and precise diagnoses.

This and previous MJFF-funded work regarding alpha-synuclein in areas outside of the brain helped to inform the recently launched Systemic Synuclein Sampling Study (S4). S4 will evaluate alpha-synuclein in multiple locations (saliva, blood and spinal fluid, in addition to the same tissues biopsied in Dr. Munoz’s study) in individuals both with and without Parkinson’s.

At the same time, data continues to be collected through the Parkinson’s Progression Markers Initiative(PPMI) with the goal of not only finding a biomarker, but also potentially identifying risk factors for PD. In this large observational study, started in 2010, people with and without PD provide biosamples, undergo tests (including MRI and DaTscan imaging), and complete cognitive and motor examinations.

A biomarker would benefit the Parkinson’s community in more ways than just helping doctors to accurately diagnose the disease. It would also aid in tracking disease progression and measuring the effectiveness of disease-modifying therapies, which would potentially speed drug development.