In the human brain, PICALM is abundantly expressed in the microglia, oligodendrocytes, endothelial cells, neurons, vascular mural and choroid plexus cells (for further information on the localization of PICALM in the AD brain, see 3.3.1) [30,32,33,34,35,36]. The gene discussed is PICALM; the disease is Alzheimer disease.