Expanding Access to Parkinson Disease Research Through At-Home Genetic Testing

As precision medicine efforts continue to expand across neurology, genetic testing has become an increasingly important area of focus in Parkinson disease (PD) research. New findings from the Parkinson’s Foundation’s PD GENEration study, one of the largest PD genetics initiatives to date, showed that approximately 13% of participants carried a Parkinson disease–associated genetic variant, offering additional insight into the biologic drivers of disease and the potential future role of targeted therapies.

The PD GENEration study, which has enrolled more than 30,000 participants nationwide, was designed to provide no-cost genetic testing and counseling for individuals living with PD while also accelerating research into the genetic and environmental contributors to disease. A key component of the initiative has been its use of decentralized research tools, including at-home blood collection through a collaboration with Tasso, aimed at reducing barriers related to travel, mobility limitations, and traditional site-based participation.

In a recent Q&A with NeurologyLive^®, James Beck, PhD, Executive Vice President and Chief Scientific Officer of the Parkinson’s Foundation, and Ben Casavant, PhD, co-founder and CEO of Tasso, discussed the latest findings from PD GENEration, the growing relevance of genetic testing in clinical practice, and how patient-centric research approaches may shape future large-scale neurologic studies.

NeurologyLive: Can you summarize the new key findings from the PD GENEration study, particularly the prevalence and types of Parkinson disease–associated genetic variants identified?

James Beck, PhD: We have learned several new things. The first, in a survey of clinicians, is that the majority of clinicians feel PD GENEration has significantly improved access to genetic testing for Parkinson’s disease patients and they now have more confidence in explaining the meaning of test results to their patients. We have also learned how important the return of results is to those living with Parkinson’s disease. While some may debate the current clinical utility of genetic testing for PD – it is true there are no approved gene-targeted therapies for PD, yet! – we have learned that patients find tremendous personal utility in participating in PD GENEration. They find value in learning more about their disease, how genetic results might impact their family, and knowing they are contributing to research.This also explains the tremendous growth we have seen in PD GENEration. There are now over 30,000 participants who have enrolled, and the Tasso+ device has been central to allowing us to bring this research opportunity to where people live.

How should clinicians interpret the finding that approximately 13% of participants carry a PD-related genetic variant, and what are the implications for clinical practice or patient counseling?

With a positivity rate of over 12%, it is clear that there are many people living with genetic forms of Parkinson’s – that is about 120,000 Americans.It is simply not uncommon to find patients with genetic PD in every neurologist’s clinic. Based upon anecdotes I have heard from clinicians who have tried to guess whether their patients would test positive in PD GENEration, it is evident one cannot predict who will have genetic PD or not. There is no scarlet letter for genetic PD.

The time of precision medicine in neurology is coming. I believe we will soon see success in gene-targeted therapies for PD. This will lead to a change in the standard of care for PD and wide-spread genetic testing. Neurologists need to be ready and the Parkinson’s Foundation is there to support them with counseling materials about different genetic forms of PD as well as CME training on counseling common genetic forms of PD.

What role do genetic data play in advancing our understanding of Parkinson disease pathophysiology and in guiding the development of targeted therapies?

The genetic data coming from PD GENEration and other efforts are all pointing to pathways that converge on the lysosome and cellular recycling. This allows not only for therapies targeted to the proteins of known PD genes, e.g., kinase inhibitors for LRRK2, but also to other proteins involved in lysosomal function that may not be directly involved in PD.

What is also interesting from the genetic data is what it is not telling us.Almost 88% of people with PD, come away without a positive genetic finding in PD GENEration. Genetics may yet explain the disease for more of those patients, but it is unlikely to explain it all. The environment is a likely culprit and more research into environmental causes of PD may lead to new strategies to actually prevent PD by limiting exposures to toxicants and other factors.It is certainly an exciting time in PD research.

How has the use of at-home blood collection impacted study enrollment, diversity, and overall data quality compared with traditional site-based approaches?

Ben Casavant: Clinical trials ultimately depend on the quality and completeness of the data they generate. When participation requires repeated trips to a clinic, you’re inherently limiting who can take part and how often samples are collected.

At-home blood collection changes that dynamic. By enabling people to collect samples wherever they are, at the right moment in time, you’re not only removing barriers like travel, mobility challenges, and needle anxiety, but you’re also capturing richer, more consistent data.

We’ve seen this firsthand in PD GENEration. Enrollment continues to grow, and the number of participants choosing at-home collection has more than doubled since 2024. Just as importantly, it’s helping bring in a more diverse and representative population, which is critical when you’re studying a disease as complex as Parkinson’s. 70% of the patients that participate in the PDGene study have never participated in research before, demonstrating the power that at-home testing brings by way of patient access. Better access ultimately leads to better data—and better data drives better insights.

Looking ahead, how might decentralized or patient-centric research models shape future large-scale studies in Parkinson disease and other neurologic disorders?

We’re at a turning point where research is no longer confined to the clinic, and that’s especially important in neurology. Many of these conditions make travel and frequent site visits difficult, which has historically limited both participation and the pace of discovery.

Patient-centric models flip that paradigm by bringing research to the individual, making it easier for people to participate consistently over time. What that enables is larger datasets, faster enrollment, and insights that better reflect real-world patient populations, delivering representation at a scale that has previously been nearly impossible to achieve. I believe that we will start to see trial scales both in patient participation and in the longitudinal analysis of disease progression, in turn enabling much higher-powered studies to discover novel treatments and pathways of disease.