Figure 5. Relationship of host HLA genotype to abundance of P. copri (OTU4, OTU12, and OTU934 combined relative abundance).

The HLA-class II genotype of all subjects was determined by sequence-based typing methodology (‘Materials and methods’). Groups were subdivided by the presence or absence of shared-epitope RA risk alleles (+/− SE as indicated above) and correlated with relative abundance of intestinal P. copri. A statistically significant correlation is seen between P. copri abundance and the genetic risk for rheumatoid arthritis in NORA (red stars) and healthy (blue circles) subjects by Welch’s two-tailed t test.

DOI: http://dx.doi.org/10.7554/eLife.01202.021