Principal coordinates analysis of variation between the bacterial communities present in all biopsy samples. Each data point represents an individual sample. Blue circles denote non-IBD control samples, red squares are Crohn's disease samples, green triangles are ulcerative colitis samples. Numbers indicate the donor the samples were obtained from. The paired, inflamed and non-inflamed, biopsy samples from each donor can be seen to cluster together. Figure was calculated using unweighted Fast UniFrac .