Two new studies have outlined major new findings in Parkinson's disease genetics.
New research reported in the journal Brain has shown that genetic factors could be a far more significant influence on Parkinson's disease than thought. This study included 15,000 participants and was open to individuals who had received any type of Parkinson's diagnosis.
The findings indicated that about 13 percent of study participants had a genetic form of Parkinson's disease; they carried a mutation in a Parkinson's linked gene. Previous estimates have ranged widely, but generally been lower than that. A 2009 study noted that about five percent of Parkinsons' patients had a clear genetic cause for their disease. While research has emphasized the complex nature of the disorder, more recent work has indicated that age is still the biggest risk factor for Parksinson's, and genetics may play some role in about one-quarter of cases.
This latest study, however, has indicated that 7.7 percent of study participants had a mutation in a gene called GBA1; 2.1 percent carried a PRKN mutation; while 2.4 percent had a LRRK2 genetic mutation. All of these are Parkinson's-associated genes, and may be to blame for these cases. The second phase of this study is now recruiting participants.
An unrelated study has used a fruit fly model to show that it may be possible to reverse Parkinson's symptoms. The research shown that when the activity of a gene called Cdk8 was increased in a fruit fly model of Parkinson's disease, the symptoms were reversed. The findings have been reported in Nature Communications.
Humans carry a similar gene called CDK19. Both Cdk8 and CDK18 are related to organelles known as mitochondria, the powerhouses of the cell. In some genetic forms of Parkinson's, mitochondria are known to malfunction.
"We figured out that fly Cdk8 can bypass a defect found in cells that carry a mutation that causes inherited Parkinson's," explained corresponding study author Esther Verheyen, a professor at Simon Fraser University. "This function involves helping cells get rid of defective mitochondria, which is a function that is impaired in Parkinsonism."
Cell function was restored when the researchers added fly Cdk8 or human CDK19. More work will be needed to see if this approach might work in humans, but since new treatments for Parkinson's are needed, these findings may eventually help patients.
Sources: Parkinson's Foundation, Simon Fraser University, Brain, Nature Communications
