Gene selection aims at detecting biologically relevant genes to assist biologists' research. The cDNA Microarray data used in gene selection is usually “wide”. With more than several thousand genes, but only less than a hundred of samples, many biologically irrelevant genes can gain their statistical relevance by sheer randomness. Addressing this problem goes beyond what the cDNA Microarray can offer and necessitates the use of additional information. Recent developments in bioinformatics have made various knowledge sources available, such as the KEGG pathway repository and Gene Ontology database. Integrating different types of knowledge could provide more information about genes and samples. In this work, we propose a novel approach to integrate different types of knowledge for identifying biologically relevant genes. The approach converts different types of external knowledge to its internal knowledge, which can be used to rank genes. Upon obtaining the ranking lists, it aggregates them via a probabilistic model and generates a final list. Experimental results from our study on acute lymphoblastic leukemia demonstrate the efficacy of the proposed approach and show that using different types of knowledge together can help detect biologically relevant genes.

Selection of genes that are differentially expressed and critical to a particular biological process has been a major challenge in post-array analysis. Recent development in bioinformatics has made various data sources available such as mRNA and miRNA expression profiles, biological pathway and gene annotation, etc. Efficient and effective integration of multiple data sources helps enrich our knowledge about the involved samples and genes for selecting genes bearing significant biological relevance. In this work, we studied a novel problem of multi-source gene selection: given multiple heterogeneous data sources (or data sets), select genes from expression profiles by integrating information from various data sources. We investigated how to effectively employ information contained in multiple data sources to extract an intrinsic global geometric pattern and use it in covariance analysis for gene selection. We designed and conducted experiments to systematically compare the proposed approach with representative methods in terms of statistical and biological significance, and showed the efficacy and potential of the proposed approach with promising findings.