IMPDH1 is abundant in both rod and cone photoreceptors (Cleghorn et al., 2022; Karlsson et al., 2021; Plana-Bonamaisó et al., 2020), and, unlike the typical autosomal dominant retinitis pigmentosa phenotype, whereby rods die first and cones secondarily die, patients with IMPDH1 mutations often have an early cone defect (Bennett et al., 2020; Sakti et al., 2023; Wada et al., 2005; Wendel et al., 2024). Here, IMPDH1 is linked to autosomal dominant retinitis pigmentosa.