Parkinson's is a progressive brain disorder that is almost always fatal, but the suffering can go on for years. The disease usually strikes people over age 60, but a few people get it before they reach 40. Parkinson's begins when a certain class of brain cells begins to die, cells that produce a chemical called dopamine, which your body needs.
Dopamine serves as a chemical messenger helping to control muscle activities.
In addition, transplanting dopamine-producing brain cells from dead fetuses into the brains of Parkinson's sufferers has delayed the progression of the disease in some cases. Nevertheless, Parkinson's remains a common but poorly-understood terminal disease. The causes of Parkinson's disease have been debated for 150 years, with no resolution. This led the medical community to begin thinking of Parkinson's as a disease caused by chemical exposures. Genetic causes of disease are very fashionable at the moment and it is easier to find research funds to study genes than it is to find research funds to study the effects of pesticides.