Learning Relational Descriptions of Differentially Expressed Gene Groups

This paper presents a method that uses gene ontologies (GOs), together with the paradigm of relational subgroup discovery, to find compactly described groups of genes differentially expressed in specific cancers. The groups are described by means of relational logic features, extracted from publicly available GO information, and are straightforwardly interpretable by medical experts. We applied the proposed method to three gene expression data sets with the following respective sets of sample classes: 1) acute lymphoblastic leukemia (ALL) versus acute myeloid leukemia (AML); 2) seven subtypes of ALL; and 3) 14 different types of cancers. Significant number of discovered groups of genes had a description that highlighted the underlying biological process responsible for distinguishing one class from the other classes. The quality of the discovered descriptions was also verified by cross validation. We believe that the presented approach will significantly contribute to the application of relational machine learning to gene expression analysis, given the expected increase in both the quality and quantity of gene/protein annotations in the near future.