[MIM 617 493]

Acronym for NEurodevelopmental Disorder with Involuntary Movements.

Very rare. Recessive autosomal transmission of a mutation of the GNAO1 gene (16q13). Other mutations in this gene produce early childhood epileptic encephalopathy 17 (see Ohtahara syndrome) or GNAO1 encephalopathy (see this term).

Clinical presentation:

-        developmental delay that appears in early childhood

-        involuntary movements (chorea, athetosis) sometimes severe and hyperkinetic, often exacerbated by stress, fever or intercurrent infection

-        generally normal brain MRI (thin corpus callosum)

-        sometimes epilepsy

Movement disorders are sometimes improved by topiramate or deep brain stimulation.

Anesthetic implications:

developmental delay, severe polyhandicap, epilepsy

References :

-        Saitsu H, Fukai R, Ben-Zeev B, Sakai Y, Mimaki M et al.
Phenotypic spectrum of GNAO1 variants: epileptic encephalopathy to involuntary movements with severe developmental delay. 
Eur J Hum Genet 2016; 24: 129-34.

Updated: January 2020