title: vHOG, a multispecies vertebrate ontology of homologous organs groups.
abstract: BACKGROUND
  Most anatomical ontologies are species-specific, whereas a framework for comparative studies is needed. We describe the vertebrate Homologous Organs Groups ontology, vHOG, used to compare expression patterns between species.
  
  
  RESULTS
  vHOG is a multispecies anatomical ontology for the vertebrate lineage. It is based on the HOGs used in the Bgee database of gene expression evolution. vHOG version 1.4 includes 1184 terms, follows OBO principles and is based on the Common Anatomy Reference Ontology (CARO). vHOG only describes structures with historical homology relations between model vertebrate species. The mapping to species-specific anatomical ontologies is provided as a separate file, so that no homology hypothesis is stated within the ontology itself. Each mapping has been manually reviewed, and we provide support codes and references when available.
  
  
  METHODS
  vHOG is available from the Bgee download site (http://bgee.unil.ch/), as well as from the OBO Foundry and the NCBO Bioportal websites.
  
  
  BACKGROUND
  bgee@isb-sib.ch; frederic.bastian@unil.ch.
authors.affiliation: Department of Ecology and Evolution, Biophore, University of Lausanne, Lausanne, Switzerland.
authors.forename: Anne
authors.initials: A
authors.lastname: Niknejad
authors.forename: Aurélie
authors.initials: A
authors.lastname: Comte
authors.forename: Gilles
authors.initials: G
authors.lastname: Parmentier
authors.forename: Julien
authors.initials: J
authors.lastname: Roux
authors.forename: Frederic B
authors.initials: FB
authors.lastname: Bastian
authors.forename: Marc
authors.initials: M
authors.lastname: Robinson-Rechavi
mesh_terms: D000818:Animals; D005075:Biological Evolution; D019295:Computational Biology / Q000379:methods; D016208:Databases, Factual; D015870:Gene Expression; D009626:Terminology as Topic; D014714:Vertebrates / Q000033:anatomy & histology* / Q000145:classification; D018875:Vocabulary, Controlled