OR1A1 belongs to the G protein coupled receptor 1 family and functions as an odorant receptor. Olfactory receptors interact with odorant molecules in the nose, to initiate a neuronal response that triggers the perception of a smell. The olfactory receptor proteins are members of a large family of G protein coupled receptors (GPCR) arising from single coding-exon genes. Olfactory receptors share a 7 transmembrane domain structure with many neurotransmitter and hormone receptors and are responsible for the recognition and G protein mediated transduction of odorant signals. The olfactory receptor gene family is the largest in the genome. The nomenclature assigned to the olfactory receptor genes and proteins for this organism is independent of other organisms.