Measures of bacterial diversity in the mucosal biopsies. 3A) Rarefaction analysis showing number of phylotypes observed with increasing sequencing effort across all patient cohorts. Data points show the observed diversity after each individual biopsy sample was incorporated into the analysis. Colour-coded errors bars show 95% confidence intervals for each patient cohort. Note that, as each patient is incorporated into the analysis, the gap between the number of phylotypes observed in non-IBD patients compared to IBD patients grows larger. The reduction in species richness appeared to be particularly significant in CD patients. Number of sequences per sample: Non-IBD controls = 252-489, CD Inflamed = 248-342, CD Non-inflamed = 287-445, UC Inflamed = 267-469, UC Non-inflamed = 286-499. 3B) Mean Shannon diversity indices (SDI) calculated from the individual biopsies for each sample type. Significantly reduced SDI compared to non-IBD control samples are indicated by * (p = < 0.05). Error bars indicate standard deviation from the mean.