Actor Michael J. Fox Hails ‘Breakthrough’ Parkinson’s Test

NEW YORK — Actor Michael J. Fox is hailing a newly developed spinal fluid test as “one of the most significant breakthroughs in decades” when it comes to understanding Parkinson’s disease.

In an op-ed in USA Today and on the website of the foundation he launched in the fall of 2000, Fox calls a new, “remarkably accurate” tool that can reveal a key pathology of the disease in brain and body cells “an enormous leap forward.”

Fox, who became a beloved television star through his work on seven seasons of NBC’s “Family Ties” in the 1980s, and also starred in 10 feature films, was diagnosed with young-onset Parkinson’s disease after he developed a tremor in his pinky finger.

At the time of the shocking diagnosis, Fox was making the movie “Doc Hollywood.” The year was 1991. The actor was just 29 years old at the time.

The discovery of the new tool, which identifies abnormal alpha-synuclein — known as the “Parkinson’s protein” — was announced last month when the research was published in the scientific journal The Lancet Neurology.

According to Fox, who is now 61, and his foundation, the discovery “opens a new chapter for research, with the promise of a future where every person living with Parkinson’s can expect improved care and treatments — and newly diagnosed individuals may never advance to full-blown symptoms.”   

The tool, called the α-synuclein seed amplification assay, 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. 

According to the Michael J. Fox Foundation, the assay can confirm the presence of abnormal alpha-synuclein, detected in most people with PD, with astonishing accuracy: 93% 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,” said Todd Sherer, Ph.D., chief mission officer with the foundation.

The biomarker breakthrough was achieved by an international coalition of scientists led by the foundation and its landmark clinical study, Parkinson’s Progression Markers Initiative. Funding for the research was provided by the Michael J. Fox Foundation for Parkinson’s Research.

A protein normally found in the nervous system, alpha-synuclein — like amyloid in Alzheimer’s disease — can start to misfold and clump, damaging neurons and causing Parkinson’s disease to develop. It has previously been possible to confirm the presence of these clumps only through postmortem analysis.  

The new tool cleverly takes advantage of a telling characteristic of alpha-synuclein that is pathologic: it causes nearby, normal alpha-synuclein to also misfold and clump.

For the assay, spinal fluid samples are prepared with a fluorescing agent that lights up if alpha-synuclein clumps form. Normal alpha-synuclein is then seeded into the spinal fluid sample. If abnormal alpha-synuclein is present in the sample, clumps form and the dye lights up. If no abnormal alpha-synuclein is present, the dye doesn’t fluoresce. 

After being tested in small, independent studies, in 2022 the assay was validated in the large, well-characterized cohort of the Parkinson’s Progression Markers Initiative.

The validation was carried out in some 1,123 samples of spinal fluid contributed by Parkinson’s Progression Markers Initiative participants. 

Steady and critical advances in the pursuit of a reliable and accurate biomarker test have been the hallmark of the PPMI, which was built for this purpose. The discovery enabled by the new test is the latest, and most significant, finding to date from the study. 

“I’m moved, humbled and blown away by this breakthrough, which is already transforming research and care, with enormous opportunity to grow from here,” Fox said. “I’m so grateful for the support of patients, families and researchers who are in it with us as we continue to kick down doors on the path to eradicating Parkinson’s once and for all.”

Dan can be reached at [email protected] and @DanMcCue