GRK1 and vitamin A deficiency: This occurs, for example, in vitamin A deficiency [11], fundus albipunctatus (RDH5-retinopathy) [12] and Oguchi disease (SAG- or GRK1-retinopathy) [13] and in some cases of rod-cone dystrophy including early stages of Bothnia dystrophy (RLBP1-retinopathy).