|
Causes
Parkinson's disease occurs when dopamine-producing nerve cells die in a region of the brain that plays a critical role in smooth motor movements. The underlying causes for the brain cell death are unknown, though some interplay of environmental factors and genetic susceptibility is thought to be responsible. Because people who live in rural areas and drink well water seem to have a higher incidence of the disease, for example, researchers have explored whether exposure to pesticides might play a role. Exposure to heavy metals such as copper has also been associated with a higher incidence of the disease.
In a small number of cases, genetic mutations are responsible for the disease. Flawed copies of the parkin gene, for instance, allow a buildup of defective proteins in brain cells that may contribute to neuron death in a small number of people. In addition, new research suggests that a defect in a different gene that influences the level of phosphates in brain cells may be responsible for about a third of all cases of Parkinson's in Jews of eastern European descent as well as in a significant percentage of Arabs and North Africans. Other genes for Parkinson's disease have been identified as well.
|
