Circumventing the cut-off for enrichment analysis.

Three tools for threshold-free enrichment analysis of microarray data are introduced: GSEA (gene set enrichment analysis), ermineJ and DRIM (discovering rank imbalanced motifs). GSEA offers an interface to a specific algorithm and a well-defined pipeline for the identifying enrichment in diverse gene sets and the creation of signature profiles. ermineJ offers a combined front end to three different algorithms, two of which perform a cut-off-free enrichment analysis. DRIM comprises an implementation of a new algorithm and is specifically designed for the search of new transcription-factor-binding sites based on expression patterns. Together, these tools demonstrate an emerging trend in high-throughput data analysis-the joint analysis of raw results with external knowledge.