Scientists from the National Institutes of Health (NIH) have identified six new genetic factors that may predict Parkinson's disease. The study was published in the July 27 issue of Nature Genetics.
Parkinson's disease is a chronic disease characterized by a variety of movement issues such as shaking or tremors, difficulty eating, and difficulty walking and doing other simple tasks. Neurologically, it involves a deficit of dopamine and is part of a larger group of conditions called motor system disorders. This disease primarily affects people over 50 years old.
Although the exact mechanism and cause of Parkinson's is unclear, scientists have identified risk factors that predict a person's susceptibility to developing the disorder. NIH scientists used data from more than 18,000 patients to identify 26 different genetic risk factors including the six new factors that have not been previously established.
"Unraveling the genetic underpinnings of Parkinson's is vital to understanding the multiple mechanisms involved in this complex disease, and hopefully, may one day lead to effective therapies," said NIH National Institute on Aging scientist and senior author of the study Andrew Singleton.
Singleton and his team used data from existing genome-wide association studies to identify the genetic risk variants which could increase a person's chance of developing Parkinson's by up to three times.
Scientists used the gene chip NeuroX, which contains approximately 24,000 common gene variants associated with a variety of neurodegenerative disorders, to compare genetic regions of Parkinson's disease patients and control subjects and confirm their results. They confirmed two dozen variants as risk factors for Parkinson's disease.
"The replication phase of the study demonstrates the utility of the NeuroX chip for unlocking the secrets of neurodegenerative disorders," said Margaret Sutherland, a program director at the National Institute of Neurological Disorders and Stroke. "The power of these high tech, data-driven genomic methods allows scientists to find the needle in the haystack that may ultimately lead to new treatments."
Some of these factors have been associated with Gaucher's disease and regulation of inflammation and dopamine. They have also been associated with alpha-synuclein, a protein found in the brains of some Parkinson's patients. Although the gene variants have been identified, more study is needed to identify the mechanisms and roles of these variants in the body and the development of Parkinson's disease.
Although there is currently no cure for Parkinson's disease, a variety of medications may provide symptom relief. A combination of levodopa and carbidopa may be used to increase dopamine levels in the brain while anticholinergics may help control tremor and rigidity symptoms. Other drugs may imitate the role of dopamine in the brain. For cases that don't respond to drugs, deep brain stimulation may provide some symptomatic relief.