This is an excellent post and to me links several things together:

1. the fact that some experts believe PD begins in the gut (indeed, they have found Lewy bodies there);

2. the fact that the vagus nerve is involved, which if I am not mistaken, correlates to the nasal passage and may be why so many PDers lose their sense of smell early on;

3. if correct, as Rick said, T Rex is pooping everywhere and after twenty years things are a mess...this would explain why symptoms do not begin to show until a critical poopage threshold has been crossed (glad we use those fancy doctor words here!)

4. finally, also helps explain why everyone is so different with this disease-we all have a different tipping point and every person is chemically unique.

Glad to see folks are researching this. Thanks for the post.