ABCA4 and Stargardt disease: 2 Allikmets Allikmets R R Singh Singh N N Sun Sun H H A photoreceptor cell-specific ATP-binding transporter gene (ABCR) is mutated in recessive Stargardt macular dystrophy A photoreceptor cell-specific ATP-binding transporter gene (ABCR) is mutated in recessive Stargardt macular dystrophy Nat Genet.