But in general, immunologists and those studying autoimmunity did not become interested in the AHR until 2008, when two high impact papers identified the role of the AHR in T-cell differentiation, with certain ligands enhancing Treg generation, and others enhancing Th17 differentiation, both in vitro and in vivo (8, 9). The gene discussed is AHR; the disease is Autoimmunity.