Margaret Tuchman, Founder and President of The Parkinson Alliance, is committed to providing education about Parkinson's disease (PD) to the PD community. One facet to accomplishing this goal includes using self-report surveys to give a voice to the individual with PD. These surveys provide the opportunity to share experiences pertaining to a variety of topics related to PD and quality of life (http://www.dbs4pd.org/survey.php).
Since we receive many completed surveys with additional questions from the participant, Margaret has decided to incorporate “Frequently Asked Questions” (FAQs) to this website. Below you will ﬁnd answers to our FAQs. If you have questions or comments, please click on the following link to ask a question or provide a comment, or to obtain our contact information:
Click on a question to see the answer.
What role do genetics play in developing PD?
Most cases of Parkinson disease result from a complex interaction of environmental and genetic factors. These cases are classified as sporadic and occur in people with no apparent history of the disorder in their family. The cause of these sporadic cases remains unclear. Katrina Gwinn, M.D. a specialist in Parkinson's disease who works in the neurogenetics at the National Institute of Neurological Disorders and Stroke, has described genetic factors related to PD as “causal genes,” genes that actually cause the disease, and “associated genes,” genes that do not cause Parkinson's disease, but increase the risk of developing it.
Dr. Gwinn indicated that “a 'causal gene' alone, without the influence of other genes or environmental factors, guarantees that a person who inherits it will develop PD. This kind of genetic Parkinson's is very rare, accounting for perhaps one to two percent of people with PD... 'Associated genes,' do not cause Parkinson's on their own, but increase the risk of developing it. A person may have these genes and never develop PD, while people who do not have these genes can still end up being diagnosed with Parkinson's. However, those who have the gene are more likely to develop PD then those without it. In order for associated genes to trigger PD, they probably need to be combined with other genes or environmental factors.” (Winter 2009 issue of PDF's Newsletter, News & Review)
What are the chances that one's children will get Parkinson's disease?
Jill Marjama-Lyons M.D. and Mary J Shomon, in their book “What Your Doctor may Not Tell You About Parkinson’s Disease” include the following chart with estimates of the risk of getting Parkinson’s disease based upon family history of Parkinson’s:
Person with Parkinson’s Chance of Getting
Disease in your Family Parkinson’s Disease
None 1-2%, same as general population
Brother or Sister 5-6%
Parent only 10%
Parent and Brother or Sister 20-40%
The take home message: “If you do have other family members with Parkinson’s disease, your chances of getting Parkinson’s disease are greater than the general population, but this does not necessarily mean that you will get Parkinson’s disease. And, if you currently do have Parkinson’s disease, but no one else in your family does, it is more likely your children will not develop this condition in their lives. Even in cases where a parent and a brother or sister have been diagnosed with Parkinson’s, it is still more likely that the child of that parent will not get Parkinson’s disease” (page 28-29).