Odorant receptors genes

Mombaerts P. (1999). Odorant receptor genes in humans. Curr Opin Genet Dev 9, 315-320. 

Ressler K.J., Sullivan S.L. and Buck L. (1993). Zonal organisation of odorant receptor gene expression in the olfactory epithelium. Cell 73, 597-609. 

Here is a bit of a complication there is a lot of individual variation in the sense of human olfaction. Not everything smells the same to everyone. This holds both for the intensity of the perceived smeU as well as for its quality pleasant, floral, skunky, sweaty, or no odor at all. Andreas Keller has recently demonstrated that some significant part of this individual variation in the sense of smell derives from genetic variation in human odorant genes. Specifically, two single nucleotide polymorphisms (SNPs), leading to two amino acid substitutions in an odorant receptor, have dramatic affects on the perception of the odor of androstenone, a steroid derived from testosterone. 

Actnally the human genome contains abont 600 odorant receptor genes. However, abont 250 of these are pseudogenes that have no function. They are remnants of evolution. 

Odorant receptor one of a class of proteins encoded by several hundred genes that are receptors for odorant molecules. 

Mombaerts, P. (2001) The human repertoire of odorant receptor genes and pseudogenes. Annu. Rev. Genomics Hum. Genet. 2, 493-510. 

Ngai J., Dowling M. M., Buck L., Axel R. and Chess A. (1993) The family of genes encoding odorant receptors in the channel catfish. Cell 72, 657-666. 

This chapter will discuss the isolation of Drosophila odorant receptor (DOR) genes, how these genes have expanded our understanding of the development and functional anatomy of the olfactory system, how the odor response profiles of OSNs respond to odorants, and the mechanisms by which odor-specific activity is relayed to the brain. 

Because there was no apparent evolutionary relationship between chemoreceptor genes in the nematode and in vertebrates, it seemed at least a possibility that the insect odorant receptors would represent yet a third class of genes, unrelated to ORs in either C. elegans or vertebrates. Following this logic, Vosshall et al. 

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