Parkinson's disease is the second most common neurodegenerative disease worldwide after Alzheimer's and, according to the World Health Organization, one of the fastest-growing neurological disorders. Yet genetic research into the disease has so far relied almost exclusively on people of European ancestry. This is a problem, because the genetic causes behind the disease depend strongly on where a person comes from.
The work is part of the Global Parkinson's Genetics Program (GP2), an international consortium that brings together genetic data from people with Parkinson's around the world to advance diagnostics and precision medicine. "GP2 makes it possible to include numerous cohorts from different world regions and thus achieve a previously unattainable breadth and depth of genetic analyses," explains Prof Dr Christine Klein, adding: "Without close collaboration with the many GP2 partner centres and their cohorts, a study of this size and diversity would not have been possible."
Large regional differences in the frequency of gene variants
Two genes are at the centre of the study: GBA1 and LRRK2, which are already targets of new drugs. Both provide the blueprints for enzymes responsible for "waste disposal" in nerve cells. When they do not work properly, harmful protein deposits can accumulate and contribute to the development of Parkinson's. The study shows that while these genes are relevant worldwide, which variants occur where differs considerably from region to region.
Why this matters for patients
For the study, the team analysed genetic data from almost 100,000 people across eleven world regions. Nearly a third came from population groups that have hardly featured in previous research, such as those in Africa, Latin America and Asia. The findings have immediate consequences: if genetic diagnostics are geared only to the variants known in Europe, disease causes in people of other ancestries often go undetected. As a result, they also fall through the cracks when it comes to new, genetically targeted therapies, which so far have been tested almost exclusively in Europe and North America.
"Our study is an important first step towards a truly global precision medicine for Parkinson's. Before we can make genetically targeted therapies available worldwide, we need to understand which genetic causes play a role in different population groups and where patients potentially suitable for future genetically stratified clinical trials can be found," adds Dr Lara M. Lange.
Lübeck's contribution
Data from the University of Lübeck's own patient cohorts were included in the analyses. In addition, Prof Klein of the Institute of Neurogenetics leads the Monogenic Network within GP2, through which genetically particularly well-characterised Parkinson's cases from many international cohorts were contributed to the study. As a postdoctoral researcher at the Institute of Neurogenetics in Lübeck, Dr Lange played a key role in building this Monogenic Network and decisively shaped its structure and scientific direction. GP2 and the many participating cohorts thus form the basis that enabled the study to make the genetic diversity of Parkinson's visible across eleven population groups.
The Lancet Neurology
Observational study
People
Parkinson's disease genetics across diverse ancestries: an observational genetic study of causal and risk variants with translational implications
16-Jul-2026