Vice versa, Il‐22 secretion also serves to maintain a community rich in bacterial AHR‐ligand producers: Defective Il‐22 signaling in mice led to dysbiosis concomitant with low AHR‐ligand production and colitis susceptibility, while in humans, lower gut microbial AHR activation and a single nucleotide polymorphism linked to impaired Il‐22 function were associated with inflammatory bowel disease (Lamas et al, 2016). This evidence concerns the gene IL22 and colitis.