PARKINSON'S DISEASE
As baby boomers age, the number of those worried about getting Parkinson's If Disease (PD)--with its shuffling gait, frozen facial features and risk of depression--is on the rise. But people concerned about their own welfare because an older family member had PD can likely lay their fears to rest.
New research indicates that genes are not the determining factor in typical PD--the type that hits after age 50. The study, launched from The Parkinson's Institute in Sunnyvale, California, reviewed the medical records of more than 15,000 World War II veterans, of which 193 were twins.
"When we compared fraternal and genetic twins over the age of 50," says Caroline Tanner, M.D., Ph.D., who led the study, "we found both just as likely to develop the disease. There was no way we could stand the data on its head to reveal any hint of a genetic basis for the disease in the older group."
The opposite was true for men younger than 50, Tanner observes. Though fewer men in this group got PD--it's uncommon before middle age--identical twins were more likely to both have the disease than were fraternal twins. This points to a genetic factor in those who get the disease before age 50, says Tanner.
