Fig. 3.

Phylogenetic diversity is higher in A-secretors vs. non-A-secretors at the Operational taxonomic unit (OTU) level. Among the secretor samples, blood group A-secretors have a significant increase in the Phylogenetic Diversity (PD)-Whole Tree index compared with blood group B- and O-secretors. y-Axis shows alpha diversity as assessed by the following indexes: Richness (i.e., total number of OTUs) (P > 0.05) (A), Chao1 index (P > 0.05) (B), PD-Whole Tree Index (P = 0.041) (C), Shannon index (P > 0.05) (D). x-Axis depicts sequences per sample. Statistical comparisons were made at the maximum rarified depth.