HTR2C encodes the 5-hydroxytryptamine 2C receptor, a G-protein coupled receptor that serves as the primary serotonin receptor in the brain, particularly enriched in the hypothalamus and brainstem 1. The receptor functions through Gq/11 G-protein signaling pathways, activating phospholipase C and modulating intracellular calcium release. HTR2C plays a crucial role in metabolic homeostasis, including feeding behavior and glucose metabolism 1. Loss-of-function variants in HTR2C are associated with severe obesity, hyperphagia, and maladaptive behaviors in humans, with knock-in mice displaying similar phenotypes including reduced social exploratory behavior 2. The receptor's dysfunction particularly affects appetite-suppressing proopiomelanocortin neurons, impairing their depolarization response to serotonin signaling 2. Clinically, HTR2C polymorphisms, particularly the -759C/T variant, are associated with antipsychotic-induced weight gain, though effect sizes are modest 34. The receptor has been implicated in depression pathophysiology, with reduced HTR2C expression observed in GABAergic interneurons derived from patients with major depressive disorder, and restoration of receptor activity improving neuronal deficits 5. HTR2C represents a therapeutic target for obesity treatments, though clinical applications have been limited by side effects 1.