Return of genetic results to persons with Parkinson's disease: Blessing or foe?

Parkinson's disease (PD) is increasingly understood as a biologically heterogeneous disorder, with genetic contributions ranging from high-penetrance monogenic variants to common polygenic risk. As testing becomes more accessible and clinically relevant, the key question has shifted from whether to test to whether -and how- to return results. Most PD associated variants confer probabilistic risk rather than deterministic outcomes, limiting individual-level prediction and complicating disclosure. Yet genetic findings may inform prognosis and increasingly determine eligibility for targeted therapies and clinical trials. Large-scale genetic studies show both feasibility, demand and utility with pathogenic variants identified in approximately 10-20% of patients. The ethical balance differs by context. In patients with established PD, results may provide insight and research access but require careful framing to avoid overinterpretation. In at-risk individuals, predictive testing offers limited clinical utility and can introduce psychological, familial, and insurance implications but can also allow informed family planning and participation in follow up and prevention trials. Current practice remains inconsistent, with major gaps in access to testing and counselling. Expanding disclosure without the appropriate infrastructure risks misinterpretation and widening disparities. We argue that return of genetic results in PD and at-risk individuals should be structured, and longitudinal. As clinical utility evolves, preparedness, will determine whether genetic testing becomes a part of standard care.