The core FOXG1 syndrome phenotype consists of postnatal microcephaly, severe mental retardation, absent language, dyskinesia, and corpus callosum hypogenesis.

Kortüm, F, Das, S, Flindt, M, Morris-Rosendahl, D, Stefanova, I, Goldstein A, Horn, D, Klopocki, E, Kluger, G, Martin, P, Rauch, A, Roumer, A, Saitta, S, Walsh, LE, Wieczorek, D, Uyanik, G, Kutsche, K, and Dobyns, WB. J. Med. Genet. 2011, 48(6):396-406