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HORDE - Human Olfactory Receptor Data Exploratorium

NAR Molecular Biology Database Collection entry number 366
Olender, T., Glusman, G., Feldmesser, E., Khen, M., Lancet, D.
The Weizmann Institute of Science, Rehovot, Israel

Database Description

Olfactory receptors (ORs) constitute the largest multi-gene family in multi-cellular organisms. Their evolutionary proliferation has been driven by the need to provide recognition capacity for millions of potential odorants with arbitrary chemical configuration. The Human Olfactory Receptor Data Exploratorium (, HORDE), is a database which aim to provide a comprehensive view of the human OR universe. Currently, HORDE contains 853 OR entries, of which 386 have an intact open reading frame and the rest are probable pseudogenes. This collection constitutes the most update repertoire of human ORs, deciphered by computational data-mining procedure out of the public and Celera genomic complete human genome assemblies. To allow orthologues-paralogues comparisons, HORDE includes information on ORs from other mammalian species - mouse, dog and chimpanzee. Based on phylogenetic analysis, HORDE classifies the OR repertoire into seventeen families. A HUGO-approved systematic nomenclature is provided, which affords an instant guide to the position of a gene in a phylogenetic tree: OR1A2 signifies family 1, subfamily A, member 2.

Interface. HORDE is equipped with a user-friendly interface which allows a facile data retrieval. A key feature in HORDE is a card for every OR gene, which summerizes most comprehensive information into a single HTML page, including hyperlinks to other databases. Several search engines, including BLAST tool, are supplied.

Recent Developments

Cluster viewer. The OR genes are distributed in clusters on most human chromosomes. The cluster viewer facilitates browsing of the ORs organization along human chromosomes. HORDE includes information on 135 OR clusters, ranging in size from nearly 100 ORs to singletons.

ORs expression profiles in human tissues. Expression information was integrated into HORDE from publicly available whole-genome DNA arrays, as well as ESTs and mRNAs. The ESTs and mRNAs genomic placements were further explored to reveal new information the untranslated regions (5â€™ and 3â€™ UTRs) of 154 ORs.

SNP summaries Recently we integrated into HORDE 1858 Coding Single Nucleotide Polymorphisms (cSNPs) reside in 568 ORs regions.

Go to the abstract in the NAR 2003 Database Issue.