Reduced expression of GABAergic markers in the ATRX-null forebrain. A, Real-time reverse transcriptase PCR of GABAergic markers in forebrain tissue isolated from E13.5 and P0.5 control and AtrxFoxg1Cre littermate embryos (n = 3). B, Immunofluorescence detection of Npy in the ventral telencephalon at E13.5 and E16.5 shows reduced staining levels in the ATRX-null embryos. Npy, Neuropeptide Y; Sst, somatostatin; Dlx5, distal-less homeobox 5; Gbx2, gastrulation brain homeobox 2; Lhx6, LIM homeobox protein 6; Cck, cholecystokinin. E13.5: Scale bar, 200 μm; E16.5: Scale bar, 150 μm.