Bioinformatics Program, University of California San Diego, La Jolla, California, 92093-0419, USA.|Bioinformatics Program, University of California San Diego, La Jolla, California, 92093-0419, USA.|Bioinformatics Program, University of California San Diego, La Jolla, California, 92093-0419, USA.|Bioinformatics Program, University of California San Diego, La Jolla, California, 92093-0419, USA.