Long-term outcome of early-onset GNAO1-related disease remains yet to be determined. We would suggest that prognosis of these patients should remain guarded, as 3 previously reported patients1,8 and 1 in this series have died in childhood. Furthermore, 2 reported patients have experienced definite motor regression in the early stages of disease.7,8 Identification of more patients will certainly aid delineating this newly identified disorder. Given the ever-growing disease spectrum, GNAO1 mutations should be considered in the differential diagnosis for patients with unexplained paroxysmal/nonparoxysmal early-onset hyperkinetic movement disorders, especially in the context of neurodevelopmental delay with or without epilepsy.
