Alexandria N Ardissone, Kaisa M Kemppainen and Eric W Triplett*
Evidence is growing for a role of the intestinal microbiome in the development of type 1 diabetes (T1D) in humans. The composition of the microbiota is heavily influenced by environmental and developmental factors, making the identification of disease-specific microbial signatures difficult. This review summarizes the impact of geographic location, a major confounder of the intestinal microbiota, on the discovery and validation of T1D-microbiota associations as reported in published case-control studies. Few common taxonomic associations were observed across studies and geographic locations, possibly due to the large effect of environmental confounders. In the future, a focus on single geographic regions and integration of multi-omic data will help in identifying disease signatures and potential functional biomarkers of T1D.