Identification of Olfactory Receptor Genes from Mammalian Genome Sequences

  • Yoshihito Niimura
Part of the Methods in Molecular Biology book series (MIMB, volume 1003)


Olfaction is essential for the survival of mammals. Diverse odorant molecules in the environment are detected by olfactory receptors (ORs) expressed in the olfactory epithelium of the nasal cavity. In general, mammalian genomes harbor ∼1,000 OR genes, which form the largest multigene family in mammals. The recent advances in genome sequencing technology have enabled us to computationally identify nearly complete repertoires of OR genes from various organisms. Such studies have revealed that the numbers of OR genes are highly variable among organisms depending on their living environments.

Because OR genes are intronless, it is possible to find all OR genes by conducting homology searches against the genome sequences using known OR genes as queries. However, some caution is necessary during the process of extracting intact coding sequences of OR genes and distinguishing among OR and non-OR genes. Presented here is a description of bioinformatics methods to identify the entire OR gene repertoires from mammalian genome sequences.

Key words

Olfactory receptor Multigene family Bioinformatics Mammalian genome G-protein coupled receptor 



This work was supported by grant (20770192 and 23770271) from the Ministry of Education, Culture, Sports, Science, and Technology, Japan.


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Copyright information

© Springer Science+Business Media, LLC 2013

Authors and Affiliations

  • Yoshihito Niimura
    • 1
  1. 1.Department of Bioinformatics, Medical Research InstituteTokyo Medical and Dental UniversityTokyoJapan

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