Fig. 4

Differences in codon optimization based on the HIVE-CUT and the Kazusa codon usage tables. The HIVE-CUT and the Kazusa codon usage tables were entered in the codon optimization algorithm ATGme to determine the number of suboptimal codons [39]. The Venn diagram shows how many codons were determined to be sub-optimal in the human coagulation factor IX gene for expression in CHO (Cricetulus griseus) cells. The codon usage tables used appear in Additional file 2