ANO2 (anoctamin 2) is a calcium-activated chloride channel (CaCC) with primary roles in sensory signal transduction. In olfaction, ANO2 amplifies odorant-induced depolarization by conducting chloride currents downstream of calcium-dependent signaling in olfactory receptor cells 1. ANO2 is also expressed in retinal photoreceptor cells and may contribute to light perception amplification 1. Additionally, ANO2 functions as a CaCC in taste cells, particularly type I and type II cells, where it serves as an effector downstream of P2Y receptor signaling 2. Clinically, ANO2 has emerged as an autoimmune target in multiple sclerosis (MS). Molecular mimicry between EBV nuclear antigen 1 (EBNA1) and ANO2 peptides drives cross-reactive CD4+ T cell and antibody responses in MS patients 3. ANO2-specific CD4+ T cells are significantly more frequent in MS patients, and immunization studies demonstrate that ANO2 can trigger exacerbated autoimmune encephalomyelitis 3. MS-specific IgG responses against ANO2 peptides have been documented 4, and these antibodies show cross-reactivity with EBNA1 5, supporting EBNA1 as a potential antigenic driver of MS pathology through molecular mimicry mechanisms. In ophthalmology, ANO2 genetic variants show potential clinical significance in neovascular age-related macular degeneration (AMD), with the rs2110166 SNP associated with differential response to anti-VEGF treatment 6.