CRB1 and retinitis pigmentosa 1: The Crb1KOCrb2ΔRods mouse is a model of targeted ablation of CRB2 in rods on the Crb1−/− genetic background, resulting in an early and aggravated RP phenotype, predominantly in the peripheral and central superior retina, similar to that in the Crb2ΔRods retinas [67].