Orthologous mapping of human bidirectional promoters to mouse. Promoter orthology was de-termined by identifying ortholgous genes in mouse and checking for evidence of bidirectional promoters. Genes that had a 5′ neighbor transcribed in the opposite direction are shown for promoters of Known Genes(maroon), Genbank mRNA (pink), and ESTs (red). Genes with no neighbor in mouse lack evidence for bidirectional promoters (green). Genes that could not be mapped to mouse are shown in blue.