Welcome to the home for the ontology of homology and related concepts in biology, the HOM ontology. This ontology is developped in the context of the Bgee database (http://bgee.org/), and is used to provide annotations of similarity between anatomical structure (https://github.com/BgeeDB/anatomical-similarity-annotations).
See the related publication:
An ontology to clarify homology-related concepts
Julien Roux and Marc Robinson-Rechavi
Trends in Genetics , Volume 26 , Issue 3 , 99 - 102