Zic1 encodes a zinc finger protein expressed in the developing or matured central nervous system in a highly restricted manner. Zic is expressed in granule cells that make synaptic contact with Purkinje cells. Zic1 is a gene critical to cerebellar pattern formation. The expression of Zic genes is first detected at gastrulation and at neurulation, becoming restricted to the dorsal neural ectoderm and the dorsal paraxial mesoderm. The Zic1 gene has been mapped to chromosome 9 in mouse. The 5' flanking region of the Zic1 gene contains a region-specific enhancer determined to be essential in in-vivo and in-vitro deletion analysis. The temporal profile of mRNA expression differs for each of the Zic gene products. The Drosophila odd-paired gene is highly homologous to the Zic gene family. Zic2 and Zic3 are highly similar genes. Zic2 is essential for the formation of the brain and Zic-3 is important for right and left axis formation.