On Apr. 13, 2023, in an enormous leap forward in the understanding of Parkinson’s disease (PD), researchers announced they had discovered a new tool that can reveal a key pathology of the disease: abnormal alpha-synuclein — known as the “Parkinson’s protein” — in brain and body cells.

The breakthrough was published in the scientific journal The Lancet Neurology. The tool, called the a-synuclein seeding amplification assay (aSyn-SAA), can detect pathology in spinal fluid not only of people diagnosed with Parkinson’s, but also in individuals who have not yet been diagnosed or shown clinical symptoms of the disease, but are at a high risk of developing it.

The assay can confirm the presence of abnormal alpha-synuclein, detected in most people with PD, with astonishing accuracy: 93 percent of people with Parkinson’s who participated in the assay were proven to have abnormal alpha-synuclein. “We’ve never previously been able to see in a living person whether they have this alpha-synuclein biological change happening in their body,” says Todd Sherer, PhD, chief mission officer, The The Michael J. Fox Foundation (MJFF).