GNAO1 and Encephalopathy: This analysis separates GNAO1 encephalopathy cases into those with a very early onset (<10 postnatal days; represented by G45E, L199P, F275S, and I279N), early onset (≥10 days, <3 postnatal months; G40R, Q52R, D174G, G203R, A227V, Y231C, and N270H), late onset (≥3 months, <2 postnatal years; S47G, R209C, E237K, and E246K), and very late onset (≥2 postnatal years; C215Y and Q233P) (Supplemental Table 1).