Parkinson's disease and, recently, depression, especially bipolar
depression, have been shown to have very specific sites of neuronal
degeneration. It has also been speculated that both PD and depression
might be due to a virual infection, probably the rabies-like Borna virus.
The Borna virus is apparently evolutionarily ancient due to its conserved
genetic sequence. Yet, it seems to be that it might cause very specific
yet different diseases. The etiology of PD and perhaps depression, has
been shown to include a genetic component of the victim. This leads to
the following conjecture: The victim's genetic composition affects the
site of the disease, but the Borna virus is the causative agent. As a
corollary, this suggests that one might be able to correlate the victim's
genetics with a neurotrophic element that determines the site of the
disease.
Are there any comments or elaborations?