Figure 2From: Comparative analyses of bidirectional promoters in vertebratesMapping the evolutionary history of bidirectional promoters. Human bidirectional promoters were mapped by their surrounding orthologous genes. Examples marked by a red bar correspond to orthologous bidirectional promoters, where both human genes are present in another species (Type I regions). Regions containing only one ortholog in the pair and no bidirectional promoter (Type II) are marked in black. Type III regions have no evidence of either orthologous gene identified in the human annotations.Back to article page