Parkinson's disease may also affect patients' eyesight, in addition to the distinctive motor problems, according to new research.
Scientists from the University of York have identified a link between the genetic mutations responsible for the neurodegenerative disease and issues with vision.
As part of their study, which is published in the latest edition of the Human Molecular Genetics journal, the team assessed nerve-cell deterioration in the common fruit fly, Drosophila. This species was chosen as the subject of the investigation because it has similar levels of dopamine in its visual system as the human eye.
They discovered a gradual loss of visual function in those that were carrying the gene responsible for Parkinson's.
Dr Chris Elliott, who led the study, said: "This is a significant step forward as it will help to identify those people with Parkinson's who may be at greater risk of changes in their vision."
The team now hopes to continue this research and confirm the results are applicable to humans.
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