Retinol dehydrogenase 12 (RDH12) is a member of the short-chain dehydrogenase/reductase (SDR) superfamily. This NADPH-dependent enzyme is highly expressed in the photoreceptor inner segments of the retina, where it functions as a key component of the visual cycle. RDH12 catalyzes the reduction of all-trans-retinal to all-trans-retinol, a critical step in regenerating the visual chromophore 11-cis-retinal. Mutations in the RDH12 gene cause autosomal recessive retinitis pigmentosa (RP) and Leber congenital amaurosis (LCA), severe inherited retinal dystrophies characterized by early-onset vision loss and photoreceptor degeneration. Loss of RDH12 activity leads to accumulation of toxic all-trans-retinal, triggering oxidative stress and cell death. RDH12 also exhibits retinoid-binding properties and may play additional roles in lipid metabolism and cellular stress responses beyond its enzymatic function in the visual cycle.