What Causes Parkinson's

Currently there is no known cause of Parkinson’s or understanding of why some people develop Parkinson’s and not others. 

There are many theories as to the causes of Parkinson’s and it is generally thought that multiple factors are responsible. 

Through research, our understanding of the possible causes of Parkinson’s is increasing all of the time. Areas of current research include: ageing, genes, environmental factors, and chemical exposure. 


Genetic, or hereditary, Parkinson’s where Parkinson’s is passed on from one generation to the next is rare, only a very small percentage of Parkinson’s may have a direct genetic cause.

It is more common that a genetic mutation increases the risk of someone getting Parkinson's rather than directly causing it. It appears that these genetic mutations increase the risk of getting Parkinson's; however, even when there is a mutation present the chances of going on to develop Parkinson’s is low. We don't know why one person with the mutation will get Parkinson's and another will not although many believe that environmental and genetic factors interact which may cause Parkinson's.


Many scientists consider that Parkinson's results from a complex interaction between a person's genetic make-up, their life activities including environmental exposures. There is some evidence that some toxins in the environment may contribute to dopamine-producing neurons dying, leading to the development of Parkinson’s. In particular, there has been a great deal of speculation about the link between the use of some herbicides and pesticides and the development of Parkinson’s.


There are many other theories of different environmental factors leading to the development of Parkinson’s, but as yet the evidence is inconclusive. 


Advancing age, and head injuries are potential factors which increase the risk of Parkinson’s.  Unfortunately, it is generally impossible to determine the cause of Parkinson’s in an individual.

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