The analysis of gene expression was based on the publicly available ''Tissues+Mixtures'' sample data set for the Affymetrix GeneChip Human Exon 1.0 ST Array (http://www.affymetrix. com/support/technical/sample_data/exon_array_data.affx). The RMA-based probeset summaries [88] and DABG (detected above background) -values were used. Each probeset was assigned genomic coordinates using the ''Affy All Exon'' track in the UCSC browser (hg17), then was associated with any human gene from our set having an exon on the same strand that completely contained the probeset. Nearly every gene (98%) had at least one probeset.