2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/156554By analyzing the spacing of genes on chromosomes, we find that transcriptional and RNA-processing regulatory sequences outside coding regions leave footprints on the distribution of intergenic distances. Using analogies between genes on chromosomes and one-dimensional gases, we constructed a statistical null model. We have used this to estimate typical upstream and downstream regulatory sequence sizes in various species. Deviations from this model reveal bi-directional transcriptional regulatory regions in S. cerevisiae and bi-directional terminators in E. coli.Main text plus supplementary text; 26 pages, 7 figures in total. To appear in TRENDS in Genetics (May 2008)Genomicstext