Grin2d-Related Developmental and Epileptic Encephalopathy is related to cerebellar atrophy, developmental delay, and seizures and developmental and epileptic encephalopathy. An important gene associated with Grin2d-Related Developmental and Epileptic Encephalopathy is GRIN2D (Glutamate Ionotropic Receptor NMDA Type Subunit 2D). Affiliated tissues include brain.