and was the only population to show substantial expression of SST or LHX6, indicating this population is enriched for cortical interneurons. We performed principal component analysis (PCA) with the top 1% of genes based on maximum pairwise fold change across the six in vitro-derived subpopulations and mapped the in vivo-derived interneurons onto this PCA space (Figure 2E). Replicate in vitro populations show reproducible patterning, with the first PC separating progenitor (Cit−) and neuronal (Cit+) populations at each time point, and the second PC corresponding to the time point of collection. This analysis reveals that interneurons from around 100 dpc human fetal cortex most closely resemble D54 interneurons generated in vitro.
