STX1A and Alzheimer disease: To date, a number of synaptic proteins involved in presynaptic (RAB3A, SNAP25, septin-5, SV2A, synapsin I, synaptophysin, synaptotagmin, syntaxin-1a) and postsynaptic mechanisms (drebrin, neurogranin, NMDA and AMPA receptors, PSD95, synaptopodin) has been found to be altered in AD brains (19, 20) - emphasizing that synaptic integrity is diminished in AD.