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.
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.