It also found elevated DNA damage in people with a genetic mutation called LRRK2 that increases the risk for Parkinson’s disease, even in the absence of symptoms, they said.
Presently, drugs for Parkinson’s disease only help control symptoms. Sanders said she hopes that along with diagnosing Parkinson’s, the new test will help identify drugs that can reverse or halt mitochondrial DNA damage and the disease process, as well as patients who could benefit from those drugs.
Several companies including Abcam and Biogen with partner Denali Therapeutics are testing such experimental treatments.
"A new blood-based diagnostic test would be a major advancement for Parkinson’s disease, which afflicts 10 million people worldwide and is the second most common neurodegenerative disease after Alzheimer's," the researchers said.
Going forward, the researchers plan to test the diagnostic in samples from high-risk individuals who have not yet developed symptoms.