Fig. 2

Microbiota assessment on celiac (CeD) subjects and non-celiac 1st-degree relatives (NC1R). Red color legend shows values and distributions for CeD and blue color legend for NC1R (N = 101, CeD = 42, NC1R = 59). A Distribution of individual richness alpha diversity descriptor. Statistical comparison based on generalized linear mixed models (GLM, lme4:glmer function) with covariate adjustment. B Non-metric dimensional scaling (NMDS) analysis of microbiota multivariate data. A permutation-based comparison (Adonis, vegan::adonis2 function) was used to evaluate the microbial variability attributed to disease condition; statistical estimates are shown in the inbox scatter plot. Ellipses show value distribution and confidence interval at 95%. C Aitchison distance (compositional) between relative and non-relative pairs is shown in a boxplot manner. The non-relative distances outnumber several hundred times the obtained for relative pairs. For homogeneous comparison aims, there was a resampling to obtain 250 non-relative random distances to compare with < 100 retrieved from relative pairs. This procedure was tenfold, and statistical comparison was achieved every time, always significantly different (Wilcoxon Rank Sum test). D Bacterial species found to be more abundant in non-celiac controls. E Species retrieved to be more abundant in CeD subjects. Distribution of clr-based abundance is shown as violin plots; medians appear as solid lines with respective color legends. Statistical comparisons in D and E are based on generalized linear mixed models (GLM, lme4:glmer function) with covariate adjustment