3 dimensional gene expression domains. A surface rendered model of the 3D expression pattern of PAX6. Separate gene expression domains in the forebrain and hindbrain are shown in green. For reference the neural tube has been painted pale grey and the eye dark grey. The diencephalon/midbrain (D/M) boundary, the absence of staining in the zona limitans intrathalamica (zli), plus the forebrain alar-basal boundary and the striatopallidal boundary in the basal telencephalon can be seen by viewing the 3D model at various angles (a, frontal and b, lateral). (c; Additional file 3) Mpeg movie of the PAX6 expression domain.