Using a mouse model of HFD + trinitrobenzene sulfonic acid (TNBS)-induced colitis, dietary n-3 PUFAs have been shown to reduce colitis-associated disease severity and colonic mRNA expression of cytokines (IL-6, IL-17A, IL-17F, IL-21, IL-23, and IFNγ) versus corn oil in control HFD mice. The gene discussed is IL17F; the disease is colitis.