In the context of neurodevelopmental disorders, rodent in vitro data demonstrate that pathogenic GRIN2B variants alter NMDAR function,16 neuronal migration,17 dendrite morphogenesis,18, 19 and synaptic density,18, 20 which likely contribute to the aberrant circuit properties that manifest in GRIN2B‐related neurodevelopmental disorders. Here, GRIN2B is linked to neurodevelopmental disorder.