Summary of the 13 regions within the 16S rRNA gene that were used in this study.

Each sub-region was generated from the sequences in the V19 database.aThe numbers in the parentheses represent the 95% confidence interval.bSanger reads are estimated to be up to 800 bp and can be used to sequence the same molecule multiple times.cGS FLX Titanium reads average ∼400 bp (amplicon kit released 11/2009).dGS FLX reads average ∼240 bp.eIllumina reads average ∼200 bp.fThe NIH Human Microbiome Project is considering these regions for their cross-sectional studies.