For instance, altered mRNA expression of several glutamate receptors (e.g., AMPA1, AMPA3, GluR5, GluR-KA2, mGluR5), GABA receptors (e.g., GABAARβ3, GABAARδ, GABAARγ2), gap junction connexin proteins (e.g., connexin 43 and 30), and glutamate transporters (e.g., GLT-1, GLAST) have been identified in the hippocampus (Medina et al., 2016), locus coeruleus (Bernard et al., 2011), anterior cingulate cortex (Choudary et al., 2005), and left dorsolateral prefrontal cortex (Choudary et al., 2005) of patients diagnosed with MDD. Here, SLC1A2 is linked to major depressive disorder.