Indeed numerous pioneering studies have demonstrated that Cdk5 plays an indispensable role in synaptic plasticity and its deregulation is capable of initiating the early Alzheimer’s synaptic pathology, further resulting in neuronal network dysfunction and cognitive impairment and decline in AD (Qu et al., 2011; Sheng et al., 2016). This evidence concerns the gene CDK5 and Alzheimer disease.