Study finds family links in Parkinson's disease

BOSTON, Massachusetts (Reuters) -- Researchers have uncovered new evidence that Parkinson's disease can run in families, according to a study of 772 Icelanders who developed the illness after age 50.

Doctors have known for a few years that the form of Parkinson's that strikes earlier in life, as it did with U.S. television star Michael J. Fox, comes from a genetic mutation that makes them prone to the disease.

The new study, published in this week's New England Journal of Medicine, suggests that a person's genes contribute to the risk of getting Parkinson's later in life as well. The disease typically appears in older people.

A team led by Dr. Sigurlaug Sveinbjornsdottir of the National University Hospital in Reykjavik found that the risk of Parkinson's was 6.7 times higher if you had a sibling with the disease, 3.2 times greater if you had a parent with Parkinson's, and 2.7 times higher if you had a niece or nephew who was afflicted.

The researchers said the effects of the genetic mutation appear to be subtle, which is why Parkinson's frequently skips generations.

The findings were derived by cross-referencing 772 people who had developed the disease in the previous 50 years with an extensive genealogical database on 610,920 people in Iceland.

The team found no evidence that spouses were more likely to develop Parkinson's. That suggests that environmental factors such as exposure to chemicals later in life do not play a role.

But the researchers left open the possibility that environmental factors shared by family members early in life could be a factor.

"This may indicate a role for some shared environmental factor early in life," they said.

Copyright 2000 Reuters. All rights reserved. This material may not be published, broadcast, rewritten, or redistributed.

Scientists say rat study provides intriguing clues to understanding Parkinson's disease
November 5, 2000
Brain disorder pioneers win Nobel Prize
October 9, 2000
Subcommittee hears testimony on stem cell research
September 14, 2000
Parkinson's may affect nerves outside brain
September 4, 2000
Michael J. Fox bids farewell to 'Spin City,' starts Parkinson's research foundation
May 23, 2000

National Institute of Neurological Disorders and Stroke
Parkinson's Disease Foundation, Inc.
MICHAEL J FOX FOUNDATION
New England Journal of Medicine
National University Hospital; Reykjavik, Iceland
Iceland on the Web

Note: Pages will open in a new browser window

External sites are not endorsed by CNN Interactive.