Hi Horsegoer.

The chances are higher (not high) only for people with certain genetic markers and even so not everyone in familes with a marker will get PD - environmental factors are generally assumed to be part of the picture as well. That said red hair does increase the risk slightly. I'm sure others on here can elaborate. The great majority of people with Parkinsons are "idiopathic", i.e. of no known cause although theories abound as to environmental and other triggers.