For example, the gene encoding the α1 antichymotrypsin protein of Serpin family A, member 3 (SERPINA3) is an inhibitor of serine protease enzymes that has been associated with increased dementia risk [48] and is upregulated in the brain of AD patients [18,49], which increases p-tau levels and promotes Aβ deposition and formation of NFTs and can lead to neuronal death [50,51,52]. This evidence concerns the gene MAPT and Alzheimer disease.