CAST/EiJ also shows differential expression of RGS9; FOXC1; RPGRIP1; VSX1; RARB; and NSD1. Mutations within these genes have been associated with Bradyopsia; iris hypoplasia with glaucoma [63]; cone-rod dystrophy 13 [64]; corneal dystrophy [65]; Waardenburg syndrome [66]; and Sotos syndrome [67] respectively. Here, RARB is linked to Hypoplasia of the iris.