During AD, tau is aberrantly phosphorylated by multiple kinases, among which the Glycogen synthase kinase-3β (GSK3β), the cyclin-dependent protein kinase-5 (CDK5), the Dual specificity tyrosine-phosphorylation-regulated kinase 1A (DYRK1A), the Calmodulin-dependent protein kinase II (CAMKII), and the Mitogen-activated protein kinases (MAPKs) are the best known [12,13,14]. This evidence concerns the gene CDK5 and Alzheimer disease.