SAGE has been utilized extensively in the study of human disease. In the first 5 years since its inception, close to five million tags had been analyzed using this method (102) . It has been used in cancer, cardiovascular and immunological studies (74, 76, 77) . Large online SAGE libraries are now freely available to the public, with access to raw SAGE sequence data, precomputed tag extractions and several modest analysis tools. SAGEmap currently contains over two million tags from 47 SAGE libraries and is currently available at http://www.ncbi.nlm.nih.gov/sage (56) .