Developmental and Epileptic Encephalopathy 27, also known as epileptic encephalopathy, early infantile, 27, is related to grin2b-related neurodevelopmental disorder and developmental and epileptic encephalopathy 60, and has symptoms including seizures An important gene associated with Developmental and Epileptic Encephalopathy 27 is GRIN2B (Glutamate Ionotropic Receptor NMDA Type Subunit 2B), and among its related pathways/superpathways is Rett syndrome causing genes. Affiliated tissues include brain and eye, and related phenotypes are global developmental delay and microcephaly