by Rebecca Hiscott
Researchers have identified six new genetic risk factors associated with Parkinson’s disease (PD), and confirmed more than two dozen others previously thought to be associated with PD, in a meta-analysis published in the July 27 online issue of Nature Genetics.
“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,” Andrew Singleton, PhD, an investigator with the National Institutes of Health (NIH)’s National Institute on Aging and senior author of the study, said in a news release.
The researchers combined data from existing European-ancestry genome-wide association studies (GWAS) to look at a broad data set including 13,708 PD cases and 95,282 controls, for a total of 7,893,274 gene variants. Of the nearly 8 million genetic variants examined, the researchers identified 26 risk loci that may increase a person’s likelihood of developing PD. They then attempted to replicate the results in an independent sample series, which included 5,353 PD patients and 5,551 controls. Using gene chip NeuroX, which contains the sequences of about 24,000 common genetic variants believed to be associated with a number of neurodegenerative disorders, the researchers confirmed 24 genetic risk factors for PD, including six that had not been previously reported, on the basis of a P-value threshold of <0.05.
More than 50 public and private institutions, including the U.S. Department of Defense and the Michael J. Fox Foundation, contributed genetic data to the meta-analysis. “The advantage of this collaborative approach is highlighted in the identification of pathways and gene networks that may significantly increase our understanding of Parkinson’s disease,” Margaret Sutherland, PhD, a program director at the NIH’s National Institute of Neurological Disorders and Stroke, said in the news release. The NIH contributed partial funding to the study, and NIH investigators led the analysis.
The researchers also confirmed that an individual’s likelihood of developing Parkinson’s increased with the number of genetic risk factors they had. “Although the effect of each individual locus was small, risk profile analysis showed substantial cumulative risk in comparison of the highest and lowest quintiles of genetic risk,” the authors wrote.
Some of the newly identified risk loci are thought to be involved with Gaucher’s disease and regulation of inflammation, dopamine, and alpha-synuclein, the news release noted.
To learn more about the genetic variants associated with Parkinson’s disease, browse our archives here: http://bit.ly/PD-genes.