Next, we asked whether the absence of Myt1l as an exogenous factor would impact neuronal specification. At 5 WPI, we observed that almost all neurons expressed the forebrain marker FOXG1 (93.5% ± 2.7%) and GABAergic neuron markers such as GABA (89.1% ± 3.5%), DLXs (88.5% ± 1.4%) and GAD65/67 (94.4% ± 4.2%) based on immunofluorescence analysis (Fig. 2d–f). For a more comprehensive characterization, we used qPCR analysis to interrogate the expression of a series of markers in AMD-, AD- and Ngn2-iN cells cocultured with mouse glia. Virtually none of the iN cells expressed progenitor cell markers (NES, SOX1, OLIG2) (Fig. 2g(i)). The glutamatergic neuron marker vGluT1 was only detected in Ngn2-iN cells, whereas GABAergic markers (vGAT, GAD1/2, DLX1/5/6, GAT1/3) were exclusively found in AMD- and AD-iN cells. We also detected expression of PV, CB, CR, SST, VIP, NYP, NOS1, HTR3A, CCK and Reelin (RELN); however, only CB, CR and SST were consistently expressed in all biological replicates of AMD- iN cells (Fig. 2g(ii)). The expression pattern of these interneuron markers was very similar in AD-iN cells, except that RELN and
