KCNJ13 encodes Kir7.1, an inward-rectifying potassium channel with distinctive biophysical properties including very low single-channel conductance and low sensitivity to external barium/cesium blockade [UniProt]. The channel mediates potassium ion homeostasis and membrane potential regulation, with particular importance in retinal pigment epithelium (RPE) and tracheal smooth muscle. In the RPE, KCNJ13 is essential for phagocytosis of photoreceptor outer segments; KCNJ13-knockout RPE cells demonstrate significantly reduced phagocytic activity and altered expression of phagocytosis-related genes 1. Loss of Kir7.1 in RPE causes increased oxidative stress vulnerability, leading to cell death and morphological abnormalities 2. Conditional RPE-specific loss of Kcnj13 triggers progressive photoreceptor degeneration and reduced light response 3. Beyond the retina, KCNJ13 regulates cytoskeletal organization in tracheal smooth muscle cells by maintaining ion homeostasis required for actin polymerization, acting partly through AKT-mediated signaling 4. Disease mutations cause Leber congenital amaurosis type 16 (LCA16), a rare pediatric blindness 5, and snowflake vitreoretinal degeneration, presenting with retinoschisis, macular holes, and crystalline retinopathy 6. Base-editor genome therapy successfully corrected KCNJ13 mutations in RPE cells and preserved vision in LCA16 mouse models 5.