ABCA4 and inherited retinal dystrophy: However, in other studies the percentage of retinitis pigmentosa or cone dystrophy due to ABCA4 mutations may be higher (Sung et al. 2020), mainly due to founder mutation effects and/or due to cohort particularities. While NGS technologies have greatly improved the molecular diagnosis in patients with inherited retinal dystrophies, it is desirable to develop cheaper strategies for genetic characterization.