Our present data showed that, in addition to unchanged GGT levels, hepatic transaminases (ALT and AST) were decreased in AD patients, while the AST/ALT ratio was increased, supporting the idea of a link between impaired liver function on the one hand and lower Aβ clearance, increased Aβ deposition, and decreased brain glucose metabolism on the other [27,28,29]. This evidence concerns the gene GPT and Alzheimer disease.