Data obtained in AD patients seem to be in accordance to preclinical data suggesting that the TT genotype, by increasing TGF-β1 levels, can increase the severity of cerebral amyloid angiopathy, whereas the CC genotype, by reducing TGF-β1 levels, might promote the formation of neocortical plaques. The gene discussed is TGFB1; the disease is cerebral amyloid angiopathy.