The transgenic construct contained the Tyrp1 promoter region adjoined to 2 rabbit Beta-globin exons and the cre coding region followed by a polyA signal. The Tyrp1 promoter primarily drives expression in the retinal pigment epithelium. Expression was also detected in the ciliary margin of the retina and in the neural retina. Expression was not detected in the embryonic periocular mesenchyme or the choroid.