Crumbs homologue 1 in polarity and blindness.

Several retinal dystrophies, including retinitis pigmentosa type 12 and Leber congenital amaurosis, are caused by a large variety of mutations in the CRB1 (Crumbs homologue 1) gene. This discovery led to an increased focus on the function of CRB1 and the Drosophila homologue Crumbs. In the present study, we review the current knowledge on Crumbs and its vertebrate homologues, their function in cell polarity and their pathogenicity in retinal degeneration.