Causes of Parkinson’s

Theories About What Causes Parkinson’s

The cause of Parkinson’s disease is still unknown, although there is some evidence for the role of genetics, environmental factors, or a combination of both. It is also possible that there may be more than one cause of the disease. Scientists generally believe that both genetics and environment interact to cause Parkinson’s disease in most people who have it.

Currently, there is an enormous amount of research directed at producing more answers about what causes Parkinson’s disease and how it might be prevented or cured. When physicians diagnose Parkinson’s, they often describe it as idiopathic (ID-ee-oh-PATH-ik). This simply means that the cause of the disease is not known.

Genetic factors

Scientists estimate that less than 10% of cases of Parkinson’s disease are primarily due to genetic causes. The most common genetic effect that triggers Parkinson’s disease is mutation in a gene called LRRK2. The LRRK2 defect is particularly frequent in families of North African or Jewish descent. Mutations in alpha-synuclein have also been found to trigger Parkinson’s, but these are quite rare. In most cases, no primary genetic cause can be found. Watch Beate Ritz’ presentation on Genes & the Environment here.

Environmental factors

Certain environmental factors, such as significant exposure to pesticides or certain heavy metals and repeated head injuries, can increase risk of Parkinson’s. Most people do not have a clear environmental cause for their Parkinson’s diagnosis, and because many years can pass between exposure to an environmental factor and the appearance of Parkinson’s disease symptoms, the connection is often difficult to establish. However, it seems likely that environmental factors do influence the development of Parkinson’s, perhaps particularly in people who also have a genetic susceptibility.

Other risk factors

There are other things that put an individual at higher risk for developing Parkinson’s. The main risk factor is age, because Parkinson’s disease is most commonly found in adults over the age of 50 (although diagnoses can occur in much younger people). Men also have a higher risk of Parkinson’s disease than women. Parkinson’s disease often seems to affect Caucasians more than African Americans or Asians. The actual links between any of these factors and Parkinson’s disease are not completely understood.


To get a more in-depth understanding of Parkinson’s disease, its effect on the lives of those who have it, and how it can be treated, follow the links below: