We have previously shown that the CBL neurotrophic peptide mixture is capable of reducing behavioral deficits in an APP tg mouse model of AD-like pathology [13] by blocking CDK5 and GSK3β [16], resulting in decreased APP maturation and Aβ biosynthesis [30], increased neurogenesis [15] and synaptic formation [13]. This evidence concerns the gene CDK5 and Alzheimer disease.