The Quote below appears to imply that that there is a Chemical or biological cause for PD. In some sense on would wish it were so! Then one could finally find ways to avoid or perhaps even cure the disease. The fact is, aside for the immediate effects of MTPT and perhaps a few other chemical causes, there are no other direct causative agents. Trauma to the head has been mentioned here a number of times but the evidence is fairly weak. Hereditity seems to play a weak role. So, the bottomline is that it looks like nobody really knows the cause. __________________________________________________________________________________________________ Hello Bill, You seem to know your way around statistics so here is some numbers to work on. I joined a new Young Parkinson's Support Group and there is an ex-marine age 32 who is in stage 3 of PD. He believes that his PD started with an Anthrax shot he was given. He told the group that in his room he has a picture of his 12 man squad and out of the 12 there are 3 men who have PD and a fourth man who died of another neuro disease. Three out of twelve. Are those high odds or what? K-F cg Carline