In the examination of all 75 RP disease-causing genes, we found an enrichment of the phototransduction (Cnga1, Cngb3, Guca1b, Pde6a, Pde6b, Rho, Sag) and rod retinoid pathway genes (Abca4, Lrat, Rdh12, Rbp3, Rlbp1, Rpe65) (Table 4). This evidence concerns the gene GUCA1B and retinitis pigmentosa 1.