The small-eye mutation results in abnormalities in the lateral cortical migratory stream.

Mice with homozygous mutations of the Pax-6 gene exhibit a constellation of developmental problems including the absence of eyes and nasal cavities and problems in the movement of neuroblasts out of the germinal epithelium. In this paper, we demonstrate further disturbances in neuronal migration. Normally, cells produced along the lateral ventricles move laterally across the pallium, ultimately coming to reside in the lateral neocortex and primary olfactory cortex. In mutant animals, these cells continue to migrate to the pial surface of the brain.