Anumantha Kanthasamy, Ph.D.
Iowa State University
NIEHS grantees developed an accurate and noninvasive assay to diagnose Parkinson’s disease, a neurodegenerative condition that is misdiagnosed more than 20% of the time. The new assay is an improvement over current Parkinson’s disease diagnostic tests that are often inaccurate, invasive, or can only be conducted after death. The study authors state that if validated in larger cohort studies, the assay could facilitate earlier Parkinson’s disease diagnosis and treatment.
A key marker of Parkinson’s disease is the misfolding and clumping of the protein alpha-synuclein (alpha-syn) in the brain and other tissues. The researchers previously developed an assay to detect misfolded alpha-syn levels in postmortem brain and cerebrospinal fluid. Here, they extended and optimized the assay to assess skin samples from confirmed Parkinson’s disease cases and controls. Researchers analyzed frozen skin samples from 25 cases and 25 controls, and skin samples preserved in formaldehyde from 12 cases and 12 controls.
Skin samples from Parkinson’s disease cases had significantly higher levels of misfolded alpha-syn compared to controls. Among frozen skin samples, the assay correctly identified case and control samples 96% of the time. Among formaldehyde-preserved skin samples, the assay identified cases and controls with 75% and 83% accuracy, respectively.
According to the authors, study results clearly demonstrate that levels of misfolded alpha-syn in skin can serve as a diagnostic marker for Parkinson’s disease, providing a critical tool for initiating early intervention.
Citation: Manne S, Kondru N, Jin H, Serrano GE, Anantharam V, Kanthasamy A, Adler CH, Beach TG, Kanthasamy AG. 2020. Blinded RT-QuIC analysis of alpha-synuclein biomarker in skin tissue from Parkinson's disease patients. Mov Disord; doi: 10.1002/mds.28242 [Online 22 Sep 2020].