Fig. 2

Structure and length of OR gene features. Barplots of the longest transcript for each OR gene, split by 5′ untranslated region (UTR), coding sequence (CDS) and 3′ UTR, in kilobases. Genes are ordered by decreasing total transcript length. Genes have been split into protein-coding (top) and pseudogenes (bottom), and by species (human on the left, mouse on the right). For pseudogenes, the CDS region of the barplot corresponds to the pseudogenic CDS. Above the barplot, a representative schematic of the OR gene structure; exons are shown as boxes and introns as connecting lines. Above the exons, bars indicate the number of genes with the corresponding number of exons; single-exon transcripts are rightmost, containing the CDS, and increasing number of exons progress to the left. The pie chart indicates the proportion of genes that are protein-coding or pseudogenised. iATG = initiation methionine of the open reading frame