%0 Case Reports %T Neurodevelopmental disorder associated with de novo SCN3A pathogenic variants: two new cases and review of the literature. %A Inuzuka LM %A Macedo-Souza LI %A Della-Ripa B %A Cabral KSS %A Monteiro F %A Kitajima JP %A de Souza Godoy LF %A de Souza Delgado D %A Kok F %A Garzon E %J Brain Dev %V 42 %N 2 %D Feb 2020 %M 31677917 %F 2.272 %R 10.1016/j.braindev.2019.09.004 %X SCN3A was recently recognized as a gene associated with neurodevelopmental disorder and epilepsy. We present two additional patients with a novel de novo SCN3A pathogenic variant, and a review of all published cases of de novo variants. In one of our patients brain magnetic resonance imaging (MRI) disclosed a severe polymicrogyria and in the other it was normal. The clinical phenotype was characterized by a severe developmental delay and refractory epilepsy in the patient with polymicrogyria and intellectual disability with autistic features and pharmacoresponsive epilepsy in the subject with normal MRI. Polymicrogyria, a disorder of progenitor cells proliferation and migration, is an unanticipated finding for an ion channel dysfunction.