Cell Type Proportions across Sites in Organoid and Primary Tissue Samples. Cell type proportions across the 3 sites at A) day 14 and B) day 84. Each differentiation replicate (Diff. Rep.) is a unique dissociation from a single organoid from an independent differentiation. C) Cell type proportions from 3 separate day 56 organoids harvested from the same differentiation replicate at UNC. D). Cell type proportion reported by (Polioudakis et al. 2019) from primary fetal tissue at similar developmental stages. End (Endothelial), ExDp1 (Excitatory deep layer 1), ExDp2 (Excitatory deep layer 1), ExM (Maturing excitatory), ExM-U (Maturing excitatory upper enriched), ExN (Migrating excitatory), InCGE (Interneuron Caudal Ganglionic Eminence), InMGE (Interneuron Medial Ganglionic Eminence), IP (Intermediate progenitors), Mic (Microglia), OPC (Oligodendrocyte progenitor cell), oRG (Outer radial glia), Per (Pericyte), PgG2M (Cycling progenitors(G2/M phase), PgS (Cycling progenitors (S phase)), vRG (Ventricular radial glia). E) Cell type proportions reported by (Bhaduri et al. 2020). Each sample is a unique primary tissue donor ordered from earlier to later developmental stages. CS (Carnegie Stage), GW (gestation week).