The ventral MGE is not a major source for cortical interneurons based on fate mapping using Shh-Cre (Flandin et al., 2010). Thus, the dorsal MGE must be the source of most MGE-derived cortical and striatal GABAergic interneurons. It is poorly understood whether these cell types are generated from distinct subregions, from distinct but intermixed progenitors, or from the same progenitors in a stochastic or temporally modulated program. While the same neuroepithelial progenitor can generate different types of cortical interneurons (PV and Sst)(Brown et al., 2011), it is not known whether cortical and striatal interneurons are derived from the same progenitor.
