1. From the Prenatal Pediatrics Institute (O.F., K.C., Y.K., S.B.M.), Children's National Hospital; Department of Neurology (Y.K., S.B.M., T.A.), and Department of Pediatrics (Y.K., K.D., S.B.M., T.A.), The George Washington University School of Medicine and Health Sciences; Division of Neurology (Y.K., T.A.), Division of Medical Genetics (I.M., E.L.), Rare Disease Institute (I.M., E.L.), and Division of Neonatology (K.D.), Children's National Hospital, Washington, DC.