To determine whether PR dysfunction without ongoing degeneration also induces PRLΔE1 expression, we examined a model of achromatopsia (CNGB3-ACHM3; mutation in Cyclic Nucleotide Gated Channel Subunit Beta 3), a disease with impaired cone function and structure, but no rod degeneration [34, 35]. This evidence concerns the gene CNGB3 and achromatopsia.