Table 2. The clinical characteristics of patients with the GNAO1 variant (c.709G>A, p.Glu237Lys).

Ref (PMID)	Variant	Gender	Age	Inheritance	Diagnosis	MRI	Seizures	DD	ID	MD	Hypotonia	Chorea/athetosis	Treatment	Adverse effect	Outcome
28668776	C.709G>A, p.Glu237Lys	Male	3 months	De novo	Dyskinetic cerebral palsy	Progressive global atrophy	–	+		Chorea, dystonia and orofaciolingual dyskinesia		+	DBS. No exacerbations requiring intensive care unit admission were observed following DBS. Decrease of orofaciolingual dyskinesia, chorea and dystonia; no more hyperkinetic exacerbations; improvement of function	Postoperative complications included stimulator site infection, and lead displacement requiring reinsertion	DBS did not result in complete remission for movements; patients with short exacerbations were managed medically
29758257	C.709G>A, p.Glu237Lys	Male	3 months	De novo			–			+			Tetrabenazine
	C.709G>A, p.Glu237Lys	Male	4 months	De novo			–			+			Levetiracetam
29935962	C.709G>A, p.Glu237Lys	Female	4 years	De novo	MD	Normal	–	+		Decreased spontaneous movement; mild dystonic features	+
30103967	C.709G>A, p.Glu237Lys	Male	–	De novo	Severe hyperkinesia	Small medio-putaminal atrophy	–	+		Recurrent episodes of hyperkinesia with dystonia; choreoathetosis, ballism, severe orofacial dyskinesia and dysphagia with concomitant autonomic features	+	+	DBS. Almost complete remission of hyperkinesia and dystonia at rest; improvement of non-verbal communication, hand function, and mobility	6.5 y reimplantation due to hardware infection	DBS almost complete remission
	C.709G>A, p.Glu237Lys	Male	–	Unknown	Severe hyperkinesia	Normal	–	+				+	DBS. Significant effects on the hyperkinetic, choreatic features	Patient suffered from recurrent loss of beneficial effects due to dysfunctions of the DBS system requiring several hardware replacements	At 14.8 y, the child died due to the refractory worsening of the hyperkinesia
34441836	C.709G>A, p.Glu237Lys	Female	15 years	Not shown	Dystonia		–	+	+	+			DBS, trihexyphenidyl
	C.709G>A, p.Glu237Lys	Female	3 years	Not shown	Dystonia		–	+		+			Trihexyphenidyl, Tetrabenazine
This report	C.709G>A, p.Glu237Lys	Male	5 years	De novo	MD	Normal	–	+	+		+	+	OXC	The complex MDs were reduced significantly

y, years; MRI, magnetic resonance imaging; DD, developmental delay; ID, intellectual disability; MD, movement disorder; DBS, deep brain stimulation; OXC, oxcarbazepine; ‘+’, positive; ‘–’, negative.