Table 1 outlines her phenotypic features using Human Phenotype Ontology (HPO) terms. Before whole-exome sequencing (WES), an infantile epileptic encephalopathy panel that did not include SCN8A was ordered for this proband. The results showed a variant of uncertain significance in exon 3 of the GRIN2A gene that encodes the glutamate ionotropic receptor N-methyl-d-aspartate (NMDA)-type subunit 2A, resulting in an amino acid change from phenylalanine to isoleucine at position 183. Here, GRIN2A is linked to Epileptic encephalopathy.