Northwestern Investigates Genetics of Parkinson's Disease

CHICAGO --- Northwestern Medicine researchers will study individuals with genetic mutations associated with Parkinson’s disease (PD) as one of 32 clinical sites of the Parkinson’s Progression Markers Initiative (PPMI), a large-scale biomarker study sponsored by The Michael J. Fox Foundation for Parkinson’s Research.

PPMI will enroll participants with a known mutation of the LRRK or SNCA [alpha-synuclein] gene. Previous research has shown these mutations are associated with Parkinson’s disease and account for a greater number of PD cases among certain ethnic populations and families, notably the LRRK2 mutation in those of Ashkenazi (Eastern European) Jewish, Basque and North African Berber descent. The insight researchers glean from these research volunteers will fortify current efforts to develop a disease-modifying therapy, something that currently eludes the field.

“Studying individuals with genetic mutations associated with Parkinson’s can accelerate our research toward a biomarker and more effective treatments,” said Tanya Simuni, M.D., the principal investigator at Northwestern. “Although known genetic mutations currently account for only five to 10 percent of all Parkinson’s cases, this population can provide invaluable information about the intricacies of the disease for all patients. 

Simuni is a professor of neurology and director of the Parkinson's Disease and Movement Disorders Center at Northwestern University Feinberg School of Medicine and a physician at Northwestern Memorial Hospital.

PPMI is studying clinical and imaging data and biological samples of people with a genetic mutation to identify biomarkers and speed clinical trials. PPMI will enroll 250 people with the LRRK2 mutation and Parkinson’s and 250 people with the mutation but without Parkinson’s. Since the SNCA mutation is rarer, the study is recruiting 50 people with Parkinson’s and the mutation and 50 people with the SNCA mutation but without PD. These participants will be followed for five years.

Interested individuals can visit www.michaeljfox.org/ppmi/genetics, call (312) 503-0755 or email pdclinicaltrials@northwestern.edu. 

PPMI is particularly interested in testing individuals of Ashkenazi (Eastern European) Jewish descent with Parkinson’s or who have a relative with the disease. The LRRK2 mutation also accounts for more PD cases in people of North African Arab Berber or Basque descent. Study sites will recruit people with the rarer SNCA mutation through familial connections.

Biomarkers — such as cholesterol level for heart disease — are substances, processes or characteristics of the body that communicate disease risk, onset and/or progression. They aid in diagnosis and disease management and help researchers stratify for clinical trials and test new drugs quicker by measuring biological changes rather than waiting for clinical improvement. There are no validated biomarkers for Parkinson’s disease, a reality researchers are hoping to change with PPMI.

Launched in 2010, PPMI is a longitudinal clinical study that collects standardized clinical, imaging and biologic data. Now taking place at 32 clinical sites around the world, the study completed initial enrollment of 423 recently diagnosed Parkinson’s patients and 196 controls in April 2013. That month PPMI began recruiting individuals with the known Parkinson’s risk factors of smell loss and REM sleep behavior disorder.

“In the fourth year of PPMI, it is evident that a large-scale biomarker study is not only possible in Parkinson’s disease, but is already yielding scientific insights that could help transform the field of Parkinson’s research,” said Todd Sherer, CEO of The Michael J. Fox Foundation. “The exceptional investigators at sites around the world, such as at Northwestern University, have created the infrastructure that allows us to make such strides by working together.”