I have hereditary form of PD with LRRK2 muted gene. Have had eye symptoms since 4th or 5th grade (slow eye focus). Bad injuries and chemicals , and stressful situations have been the triggers for adding new symptoms and worsening the symptoms thru the rest of my life. I am now in better shape than since high school. ...wish I had had some natural l-dopa back then...it would have changed my whole life. My brother had great balance all his life until about 57 yrs old when developed PD symptoms. He seemed to have no physical problems (other than he shivered at times during the day as I did...that's what we always called it....perhaps that is a myoclonic jerk?? )will have to look up that term. He was a welder/ truck driver/ mechanic and was exposed to different chemicals...he did not show having LRRK2.