Representing the UMLS® Semantic Network using OWL
(Or "What's in a Semantic Web Link?")
Vipul Kashyap
LHNCBC, National Library of Medicine, 8600 Rockville Pike, Bethesda, MD
20894
Alex Borgida
Department of Computer Science, Rutgers University, New Brunswick, NJ 08903
Abstract
The Semantic Network, a component of the Unified Medical Language System¨
(UMLS), describes core biomedical knowledge consisting of semantic types
and relationships. It is a well established, semi-formal ontology in
widespread use for over a decade. We expected to "publish" this ontology
on the Semantic Web, using OWL, with relatively little effort. However, we
ran into a number of problems concerning alternative interpretations of
the SN notation and the inability to express some of the interpretations
in OWL. We detail these problems, as a cautionary tale to others planning
to publish pre-existing ontologies on the Semantic Web, as a list of
issues to consider when describing formally concepts in any ontology, and
as a collection of criteria for evaluating alternative representations,
which could form part of a methodology of ontology development.