Apolipoprotein E4, the most prevalent genetic risk factor of Alzheimer's disease, reduced the levels of TGF-β1, -β2, as well as -β3 in the septum and that of TGF-β3 in the hippocampus suggesting the possible role of different TGF-βs in mediating the pathological effects of apolipoprotein E4 [121]. The gene discussed is TGFB1; the disease is Alzheimer disease.