http://www.spondylitis.org/members/49.aspxHere's another one :
Does the Microbiome Cause Ankylosing Spondylitis
By James Rosenbaum, MD
Winter 2011 Issue of Spondylitis Plus
This from SAA, Spondylitis Association America
A lot of research has been done between when that article was published (about 2 years ago) and now.
I don't think the HLAB27 gene dictates the microbiome, but may influence the effect that microbiome has on an individual.
And the research I've seen over and over again in the last 2 years has been human studies where they analyze the microbiome of "healthy" humans vs humans with said disease and compare the microbiome, and they see correlations. The healthy individuals will have one microbiome, the individuals with the specific disease will have a similar one, and different from the healthy one.
I've seen these correlation studies for: obesity, heart disease, diabetes, spondyloarthropathies like crohns and UC, RA, bipolar, etc.
Where the research seems to be is in understanding how the bacteria cause the various diseases, the molecular processes that lead to disease.
Animal studies have their place as well, but its been the human studies correlating bacterial gut populations with a specific disease and comparing that to healthy individuals that has caused me to sit up and pay attention.