Transcriptomes versus proteomes. Comparison of the protein composition of the venom of Costa Rican snakes reported from proteomic analysis (chart pies labelled "a") (Additional file 1: Table S4)49-52 and predicted from their venom gland transcriptomes (this work). Chart pies "b" display the relative occurrence of ORF-coding reads listed in Additional file 1: Table S4 normalized for the full-length DNA sequence of a canonical member of the protein family (%mol). Panels c show the relative abundance (mol%) of toxin families as in panels "b" but computing only toxins previously identified in the venom proteome49-52. Chart pies depicted in panels d show the relative composition (reads%) of all venom protein family hits in each of the Costa Rican snake venom gland transcriptome (Table 2). Protein family names are abbreviated as in Table 1.