Figure 1

Spurious inter-sample variation across HMP metagenomic samples. (A) Variation in the relative abundance of USiCGs across different body sites (P <10^-300, Kruskal-Wallis test). For each sample, the median relative abundance of the 76 USiCGs was used as a representative value. Boxes denote the interquartile range (IQR) between the first and third quartiles with the black line inside each box denoting the median. Whiskers extend to the lowest and highest values within 1.5 times IQR and outliers are marked in red. (B) The relative abundance of USiCGs across HMP stool samples. Each box illustrates the distribution of the relative abundances of the various USiCGs within each sample. Box range, whiskers, and outliers are defined as in panel A. See also Additional file 2: Figure S1 for the distribution within all other body sites.