GNAO1 and nervous system disorder: One example is Gαi1, a close relative of Gαo, also showing prominent CNS expression; missense mutations in G40, G45, Q52, or D173 of Gαi1 (equivalent to the mutations found in GNAO1 encephalopathy) cause dominant infantile neurological disorders, with variable degrees of developmental delay, seizures, and hypotonia (18, 46).