Funny that you should mention M. paratuberculosis. I'm reading a journal article right now about possible environmental triggers. This article says that that research on M. paratuberculosis has been inconclusive so far.
On a slightly different note, does anyone watch Oprah? Earlier this week Dr. Oz said that we are "single digit years away" from using stem cell therapy. I hope that's true--it would help so many people!