It can be refered as pathway analysis any set of techniques that use predetermined sets of genes (i.e, GO Terms, Kegg pathways) to interpret high-throughput data. The rational for performing pathways analysis is that pathway level information may be more biological meaninfull and more easily interpretable than the information provided by individual genes. Additionaly, enriched pathways can be uncovered from a collection of genes with relatively small changes in expression which can go undetected in differential gene expression analysis.
