Parkinson's disease, which affects at least 500,000 Americans, is a progressive neurologic disorder that is caused by the degeneration of nerve cells in the portion of the brain that controls movement. Scientists have long suspected genetics plays a role in the onset of the disease. In these studies, the investigators found that a mutation in the gene LRRK2 appears to occur in at least one of every 60 people who have the disease. Overall, the mutation could be responsible for up to 5 percent of Parkinson's disease in people with a family history of the disorder and may account for 1 to 2 percent of cases in individuals who do not have a family history of the disease. The researchers found a mutation in one copy of the gene can lead to the disease. The findings were published online by Lancet at 6:30 p.m. ET on January 17, 2004. Copies of the studies will be made available to the media on January 17. To request copies, journalists should email firstname.lastname@example.org.
"Among the forms of Parkinson's disease that are genetic in origin, this gene mutation causes more cases of Parkinson's disease than any other gene discovered to date," says Andrew Singleton, Ph.D., chief of the Molecular Genetics Unit in the NIA's Laboratory of Neurogenetics. "Knowing that this mutation is not only important in familial forms of dis