" from a research point of view , this is the first time we could identify what appears to be typical parkinson ' s disease cases before people develop symptoms , " says mayo clinic neuroscientist peter paget . " we know if someone inherits the trait they are going to get parkinson ' s disease . " the mutation was established by sequencing the lrrk2 gene in families with parkinson ' s from the us , norway , ireland and poland .
A genetic mutation has been linked with Parkinson's disease.