At the same time, a recent report (published after submission of this manuscript) showed that defective TGF-β reactivity, induced by conditional deletion of TGF-βRII in mature T cells, leads to enhanced autoimmunity in a lymphopenic environment, suggesting that the consequences of self-reactivity can be exacerbated in the absence of TGF-β restraint [34]. The gene discussed is TGFB1; the disease is Autoimmunity.