DICER1 and colitis: Liu et al. (2016) have identified that miRNAs are abundant in mouse and human fecal samples and present within the extracellular vesicles in the gut lumen. Moreover, depletion of the DICER enzyme (miRNA-processing enzyme) in mice leads to exacerbated colitis and disturbed microbiota (Liu et al., 2016). On the other hand, when wild-type mice receive fecal miRNA transplantation from healthy mice, it restores fecal microbes and ameliorates colitis (i.e., inflammation of the colon), showing miRNAs influence gut health (Liu et al., 2016).