These reports suggest that the reduction of effector Treg cells in RA patients may be linked to impaired IL-2/IL-2R signaling, due to both decreased expression of IL-2Rα (CD25) in Treg cells and the limited availability of IL-2 from reduced IL-2 production by autoreactive conventional CD4+ T cells. The gene discussed is IL2; the disease is rheumatoid arthritis.