the molecular reason why dCGE and LGE interneurons have different outcomes is still not clear (as of this article), especially because both regions appear to express the same genes. it may be due to a difference in the "effector of the transcription factors Dlx1 and Dlx2". the differnce between the molecular environement of the LGE/dCGE and teh MGE is largley due to Nkx2.1, a hmoeodomain-containing transcription factor that is expressed in the proliferative zone of the MGE and in the more vetrally located preoptic region. Nkx2.1 is doenregulated in internerons before they go into the cerebral cortex. without Nkx2.1, normal MGE tissue doesn't form.