A de novo GRIA3 variant with complex hyperkinetic movement disorder in a girl with developmental delay and self-limited epilepsy

Abstract

Missense variants in GRIA3 (glutamate ionotropic receptor AMPA type subunit 3), originally found in an X-linked intellectual disability syndrome in men, have been later associated with an X-linked developmental and epileptic encephalopathy presenting with developmental delay, intellectual disability, seizures, behavioral problems, dysmorphic features, movement disorders and other manifestations such as distal muscle weakness, progressive sleep disturbance, or various orthopedic abnormalities (MIM: 300699). A growing number of affected female individuals is reported.

Here we present a patient with a novel heterozygous missense de novo GRIA3 variant with intellectual deficits, self-limited epilepsy, axial hypotonia, spasticity, dystonia, choreiform movements and stereotypies.