Interestingly although IL-22 plays a protective role in mucosal diseases such as inflammatory bowel disease by enhancing barrier integrity of the intestinal tract, in other diseases such as psoriasis it has been eluded to synergise with proinflammatory cytokines and induce disease progression (Li et al., 2014; Cochez et al., 2016). The gene discussed is IL22; the disease is psoriasis.