GNAO1 and neurodevelopmental disorder: <h4>Introduction</h4>We present the case of a patient with a de novo heterozygous probably pathogenic variant c.545C>T (p.Thr182Ile) in the GNAO1 gene that is probably pathogenic in relation to a neurodevelopmental disorder and movement disorder.<h4>Case report</h4>A female patient who started at 3 months with severe neurodevelopmental delay, and subsequently myoclonus, orofacial dyskinesia, and choreoathetosis, without seizures.