High levels of this second messenger were reported also in RP mutants of genes not directly involved in cGMP regulation, i.e., Prph2 (Peripherin 2), Cngb1 (Cyclic Nucleotide Gated Channel Subunit Beta 1), Rho and Cnga3 (Cyclic Nucleotide Gated Channel Subunit alpha 3) (Arango-Gonzalez et al., 2014; Paquet-Durand et al., 2019b). This evidence concerns the gene PRPH2 and retinitis pigmentosa 1.