Fig. 5.

In situ hybridization reveals striking differences between human and rodent CNTNAP2 expression in the developing brain. In situ hybridizations for CNTNAP2 and PCDH17 were carried out on sagittal brain sections prepared from E17 mice and E21 rats. In both rodent species, CNTNAP2 was low in cortex and lacking the gradient observed in human (A and B). The diffuse signal observed in rodent is not an artifact of tissue preparation; adjacent sections hybridized with an antisense probe for Pcdh17 show tightly regionalized expression. Moreover, like human Pcdh17, prominent enrichment in anterior cortex was seen in both rodent species (C and D). Sense controls on adjacent sections gave no signal (not shown). Cb, cerebellum; Ctx, cortex; hypothal, hypothalamus; MB, midbrain; OB, olfactory bulb; Thal, thalamus; VZ, ventricular zone.