In comparison with controls, mild colitis was observed in GPR65ΔCD4 mice by subjecting to an acute colitis induced by trinitrobenzene sulfonic acid (TNBS) rectally and in a chronic colitis in Rag1–/– mice reconstituted with GPR65ΔCD4CD45RBhighCD4+ T cells in vivo, characterised by the attenuated level of proinflammatory cytokines and their transcriptional factors (Tbx21, Rorc) and decreased invasion of CD4+ T cells, neutrophils and macrophages in colon mucosa. The gene discussed is RAG1; the disease is colitis.