BEST1 encodes bestrophin 1, a calcium-activated anion channel located on chromosome 11 that mediates chloride and bicarbonate transport across cell membranes 123. The protein exists in a partially open conformation, permitting regulated anion movement 4. Beyond its canonical channel function in epithelial ion transport, BEST1 participates in calcium-dependent neurotransmitter release, including glutamate and GABA from glial cells, contributing to synaptic plasticity regulation and memory acquisition processes. BEST1 mutations cause a spectrum of inherited retinal diseases (IRDs), predominantly bestrophinopathy, vitelliform macular dystrophy, and retinitis pigmentosa 50 5. Best disease, the most common BEST1-associated condition, presents with characteristic egg-yellow fundus appearance and abnormal electrooculogram despite normal electroretinogram 6. Genetic studies demonstrate BEST1 variants account for approximately 6% of macular and cone/cone-rod dystrophies in large cohorts 7, ranking among the five most frequent IRD genes 8. Both autosomal dominant and recessive inheritance patterns occur 9. Given retinal tissue's accessibility and the established pathophysiology, BEST1 represents a promising target for emerging gene and cell-based therapeutic interventions 10.