Interestingly, blockade of the AT1 receptor by losartan has been shown to diminish TGF-β signaling, with a reduction in free TGF-β levels, tissue expression of TGF-β–responsive genes, and levels of mediators within the TGF-β signaling cascade, and to prevent aortic aneurysm development in the MFS mouse model [6]. The gene discussed is AGTR1; the disease is aortic aneurysm.