The expression of Edn2 has also been shown to be upregulated in other mouse models of RP (Bramall et al., 2013), including retina-specific Cdhr1-KO mice (Rattner and Nathans, 2005), with Prom1 and Cdhr1 having been found to interact with each other (Yang et al., 2008). Here, PROM1 is linked to retinitis pigmentosa 1.