Strept A is implicated in rheumatic heart disease and
PANDAS--Pediatric Autoimmune neuropspychiatric disorders acquired
Strep.

Tourettes, tics, anxiety disorders are implicated on chromosone l7.

Anti M antibodies are implicated on chromosone l7.

Rheumatic heart disease takes up to l0 years to manifest itself after
a strep A infection whereby anti M antibodies attack the mitral valve.
 Can this be true with Tourettes, tics, and anxiety disorders whereby
anti M antibodies attack the ganglion of the brain?  Where delayed
reaction may take up to l0 years to develop  (as in rheumatic heart
disease) in suseptable  people with a genetically deficient anti M
antibody response?

Are people with Rheumatic heart disease who carry this anti M antibody
deficiency more likely to have anxiety disorders, tics, or other
psychiatric disorder?

The idea that repeated infections with group A strep can cause
neurologic problems has received a significant amount of media
attention, but right now it is regarded primarily as hypothesis.

A 2004 review article in the journal Pediatrics can summarize much of
the current research:
PEDIATRICS Vol. 113 No. 4 April 2004, pp. 883-886
here's the link: http://pediatrics.aappublications.org/cgi/content/full/113/4/883

For more review articles, check out www.pubmed.com and try searching
for "Pandas review"

Hope this helps get you started