In this study, liver-specific Hepc KO (Cre+ Hepcf/f) mice were crossed with Cp KO (Cp−/−) mice to test the hypothesis that low levels of CP would exacerbate the toxicity of high iron levels and cause more severe degeneration, thus modeling the situation in the patient with bull's eye maculopathy. The gene discussed is CP; the disease is Bull's eye maculopathy.