On this forum I have read many posts where people are worried after being diagnosed with PD, about passing it on to their children or grandchildren. My understanding is that only 5% of people with PD have inherited it.
On the Parkinson's UK Facebook page there is a video they posted this afternoon Professor John Hardy from UCL Institute of Neurology talks about inherited PD and has some very clear diagrams that show you just how many people in a family where the PD is inherited are affected...Makes very interesting reading, and may help alleviate people's worries about passing PD on.
Of course it doesn't mean that family members won't get PD - but they will have got it because of reasons other that an 'inheritance!'
My Mum had PD and I used to be concerned about the possibility of inheriting it ......... but not since I first read about the research with the families literally 'riddled' with PD across generations.
Go to the Facebook page and listen/watch the lecture...