TAAR5 is a G protein-coupled receptor functioning primarily as an olfactory chemosensor that detects trimethylamine, a volatile trace amine with aversive odor properties 1. Upon trimethylamine binding, TAAR5 undergoes conformational changes that activate Gs-class G proteins (GNAL/GNAS), triggering adenylyl cyclase signaling and cAMP production 1. The receptor also responds to dimethylethylamine at lower efficacy 1. TAAR5 is expressed predominantly in olfactory epithelium neurons where it detects ethologically relevant volatile amines signaling spoiled food and other behavioral cues 2. However, emerging evidence reveals TAAR5 expression in multiple brain regions including the limbic system, amygdala, hippocampus, and nucleus accumbens 3. Natural sequence variants in TAAR5, particularly the Ser95Pro missense variant, significantly affect human odor perception intensity and aversion responses to fish odor 4. Functionally, TAAR5 activation in the central nervous system causes dyskinesia-like motor impairment in mice 5, suggesting involvement in movement control. Altered TAAR5 expression has been identified in Down syndrome and major depressive disorder 3, positioning TAAR5 as a potential therapeutic target for neuropsychiatric conditions beyond olfactory function.