Geneticist and molecular neuroscientist Matthew Farrer and his team have discovered a new genetic variant related to Parkinson’s disease that provides insight to better understand the disease to potentially find a treatment.

“Without understanding the fundamental molecular cause of Parkinson’s, it’s improbable that researchers will be able to develop a medication to stop the disease from steadily worsening in patients,” Farrer said.

Parkinson’s disease is a disorder that affects the nervous system and the parts of the body controlled by the nerves. It progresses relentlessly and the first symptoms may be a barely noticeable tremor in just one hand. It gradually compromises a person’s ability to function until they eventually become immobile and often develop dementia.

Over one million people are afflicted with Parkinson’s in the U.S. alone and new cases and overall numbers are steadily increasing.

Many factors, both environmental and genetic, may contribute to the development of Parkinson’s, and underlying genetic causes of the disease were unknown until recently. Most cases of Parkinson’s are not inherited but sporadic and suggested a genetic basis was improbable. Nevertheless, everything in biology has a genetic foundation and Farrer devoted his career to predicting and preventing Parkinson’s disease.

There is currently no treatment to halt or slow down Parkinson’s disease.

In the mid 1990s, researchers investigated genetic differences of those with and without Parkinson’s in hopes to find genes or genetic variants that contribute to the disease. Linkage analysis was one of the techniques that helped the team map out the genetic blueprint of Parkinson’s. It focused on rare families that had passed down neurological conditions with similar symptoms to Parkinson’s.

“Linkage studies, like the one my team and I published, have identified pathogenic mutations in over 20 genes,” Farrer said.

In requiring DNA samples of willing participants with more than two or more living, affected relatives, Farrer’s team identified a new genetic mutation of the disease called RAB32 Ser71Arg. With further analysis, the team found the new genetic mutation interacts with several proteins previously linked to early and late onset of Parkinson’s and similar dysfunction within cells.

RAB32 Ser71Arg is the first linked gene to connect the dots to prior linked discoveries, suggesting how and why mutations originated, despite creating a susceptible genetic background for Parkinson’s in later life. Such linked genes support the idea that Parkinson’s evolved to improve survival in early life because of the enhance immune response to pathogens.

Affected individuals and families from different parts of the world share an identical fragment of chromosome 6 that contains RAB32 Ser71Arg. These patients are all related ancestrally, making them distant cousins with more cousins to be identified.

More patients and family’s participation are needed in genetic research to find additional components behind Parkinson’s disease that have not yet to be discovered. With each new gene researchers discover, they can profoundly improve the ability to predict and prevent Parkinson’s.