Early studies showed that the phenotypes of heterozygous Pax6+/− mice were similar to some human inherited conditions caused by PAX6 mutants, including aniridia and Peters’ anomaly (Hill et al. 1991; Ton et al. 1991; Glaser et al. 1994; Hanson et al. 1994; Nishida et al. 1995; Davis et al. 2003; Ramaesh et al. 2003). This evidence concerns the gene PAX6 and aniridia.