SVOP (SV2-related protein) is a transmembrane transporter-like protein localized to synaptic vesicles that functions as a nucleotide-binding protein with distinct biochemical properties. Structurally, SVOP belongs to the major facilitator family and shares similarity with SV2, though it exhibits unique nucleotide-binding characteristics, demonstrating highest affinity for NAD with a single binding site spanning transmembrane domains 9-12 1. Unlike SV2, SVOP's binding site differs in location and nucleotide specificity, suggesting independent evolution of nucleotide-binding capacity within transporter families 1. Developmentally, SVOP is expressed in the nervous system beginning at the mid-neurula stage and becomes broadly distributed throughout the central nervous system, suggesting roles in neuron formation, maturation, or neuronal function 2. Functionally, SVOP likely participates in neurotransmitter vesicle dynamics through its transporter activity, though its specific substrate remains incompletely characterized. Clinically, SVOP represents a novel disease susceptibility gene for depressive symptoms. Whole-exome sequencing in 296,199 UK Biobank participants identified SVOP among six newly discovered genes associated with depressive symptom scores, with enrichment analysis linking these genes to immune response pathways and brain regions implicated in depression including the anterior cingulate cortex and orbitofrontal cortex 3. These findings suggest SVOP may contribute to depression risk through mechanisms involving immune-neurological interactions, though further functional investigation is needed to establish the molecular pathways underlying this association.