SLC2A1 and Alzheimer disease: Genetically-induced GLUT1 knockdown/knockout may have different implications for the BBB than the presumably gradual GLUT1 downregulation observed in AD—indeed, adults with rare genetic GLUT1 deficiencies do not appear to exhibit such early symptoms of AD [234], although age-related changes and interaction with Aβ load later in life have not been studied.