Our hypothesis is also supported by evidence that the blockade of EAAT in astrocytes results in elevated extracellular glutamate levels followed by neuronal death in the hippocampal CA1 and DG regions, suggesting that the elevated tonic inhibition via GAT3/4 serves as a protective mechanism in AD (Montiel et al., 2005; Héja et al., 2009). Here, SLC6A11 is linked to Alzheimer disease.