A new gene ontology-based measure for the functional similarity of gene products

Abstract

Background Although biomedical ontologies have standardized the representation of gene products across species and databases, a method for determining the functional similarities of gene products has not yet been developed. Methods We proposed a new semantic similarity measure based on Gene Ontology that considers the semantic influences from all of the ancestor terms in a graph. Our measure was compared with Resnik's measure in two applications, which were based on the association of the measure used with the gene co-expression and the protein-protein interactions. Results The results showed a considerable association between the semantic similarity and the expression correlation and between the semantic similarity and the protein-protein interactions, and our measure performed the best overall. Conclusion These results revealed the potential value of our newly proposed semantic similarity measure in studying the functional relevance of gene products.