(A) Presence of ectopic neurons in the corpus callosum of Cntnap2−/− mice. NeuN, neuronal nuclei; CTX, cortex; STR, striatum. Scale bar: 20µm. (B) Expression of Cux1, a marker for upper layer projection neurons, in somatosensory cortex of WT and Cntnap2−/− mice. Note the abnormal distribution of CUX1 positive cells in groups (arrowheads) and rows (arrow) in deep cortical layers of mutant mice. Scale bar: 50µm (C) Neuronal birth-dating analysis. BrdU injected at E16.5 was immunostained at P7. Note abnormal distribution of neurons in groups (arrowheads) and rows (arrow) in deep cortical layers of mutant animals. Scale bar: 50µm. Data are presented as mean ± S.E.M. *p<0.05, **p<0.01, ***p<0.001. n=3 mice/genotype for each age. See also Figure S2.