Yes. Although the causes are multifactorial and sometimes poorly understood, there is a hereditary component. Keep in mind, that even though a parent may have it, it does not mean that it will be necessarily passed on. The tendency, however, may be there.
Parkinsons. PD is not usually inherited and it can affect anyone. However, inherited (genetic) factors may be important in the small number of people who develop PD before the age of 50. http://patient.info/health/parkinsons-disease-leaflet.
Yes & more to learn . Current thought says many factors are involved. Pd is more common in areas with high agricultural chemical use & in those working with heavy metals or toxic chemicals. We also know that genetics are involved with several identified mutations causing higher susceptibility & rare families with dominantly inherited pd. I believe the key & cure of pd will be found using genetic breakthroughs.