SNAP25 and Alzheimer disease: Levels of CSF SNAP‐25 are increased in AD and MCI (Brinkmalm et al., 2014; Galasko et al., 2019; Wang, Zhou, & Zhang, 2018; Zhang, Therriault, et al., 2018), potentially reflecting the release of SNAP‐25 from synapses into the extracellular space.