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Updated: Jun 26, 2026

High-throughput Analysis of Mammalian Olfactory Receptors: Measurement of Receptor Activation via Luciferase Activity
Published on: June 2, 2014
Update on the olfactory receptor (OR) gene superfamily
Tsviya Olender1, Doron Lancet, Daniel W Nebert
1The Crown Human Genome Center, Department of Molecular Genetics, The Weizmann Institute of Science, Rehovot, Israel.
Abstract:
The olfactory receptor gene (OR) superfamily is the largest in the human genome. The superfamily contains 390 putatively functional genes and 465 pseudogenes arranged into 18 gene families and 300 subfamilies. Even members within the same subfamily are often located on different chromosomes. OR genes are located on all autosomes except chromosome 20, plus the X chromosome but not the Y chromosome. The gene:pseudogene ratio is lowest in human, higher in chimpanzee and highest in rat and mouse--most likely reflecting the greater need of olfaction for survival in the rodent than in the human. The OR genes undergo allelic exclusion, each sensory neurone expressing usually only one odourant receptor allele; the mechanism by which this phenomenon is regulated is not yet understood. The nomenclature system (based on evolutionary divergence of genes into families and subfamilies of the OR gene superfamily) has been designed similarly to that originally used for the CYP gene superfamily.
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