Glutamate receptor, ionotropic, delta 2, also known as GluD2, GluRδ2, or δ2, is a protein that in humans is encoded by the GRID2 gene. This protein together with GluD1 belongs to the delta receptor subtype of ionotropic glutamate receptors. They possess 14-24% sequence homology with AMPA, kainate, and NMDA subunits, but, despite their name, do not actually bind glutamate or various other glutamate agonists.