Expression of a dominant-negative form of TGFβRII (dnTGFβRII) under a CD4 promoter without a CD8 silencer leads to spontaneous activation and differentiation of both CD4 and CD8 T cells and development of autoimmune diseases at 4–6 months of age [24]; the different pathological outcomes demonstrated that the TGFβ signaling pathway is not completely abrogated by the expression of the dominant negative form of TGFβRII. This evidence concerns the gene CD8A and autoimmune disease.