GRIN2D and Epileptic encephalopathy: Furthermore, as GluN2D de novo mutations have also been linked to epileptic encephalopathies (Li et al., 2016; Camp and Yuan, 2020), and given the clear role of this subunit in CCK IN synaptic function, the heterogeneity may explain the selective loss of these neurons in some forms of experimental epilepsy (Wyeth et al., 2010; Sun et al., 2014).