![A 68-codon genetic code to incorporate four distinct non-canonical amino acids enabled by automated orthogonal mRNA design | Nature Chemistry A 68-codon genetic code to incorporate four distinct non-canonical amino acids enabled by automated orthogonal mRNA design | Nature Chemistry](https://media.springernature.com/m685/springer-static/image/art%3A10.1038%2Fs41557-021-00764-5/MediaObjects/41557_2021_764_Figa_HTML.png)
A 68-codon genetic code to incorporate four distinct non-canonical amino acids enabled by automated orthogonal mRNA design | Nature Chemistry
Preventing Dangerous Nonsense: Selection for Robustness to Transcriptional Error in Human Genes | PLOS Genetics
![Codon usage in vertebrates is associated with a low risk of acquiring nonsense mutations | Journal of Translational Medicine | Full Text Codon usage in vertebrates is associated with a low risk of acquiring nonsense mutations | Journal of Translational Medicine | Full Text](https://media.springernature.com/full/springer-static/image/art%3A10.1186%2F1479-5876-9-87/MediaObjects/12967_2011_Article_752_Fig1_HTML.jpg)
Codon usage in vertebrates is associated with a low risk of acquiring nonsense mutations | Journal of Translational Medicine | Full Text
![genetics - Why do some amino acids have more synonymous codons than others? - Biology Stack Exchange genetics - Why do some amino acids have more synonymous codons than others? - Biology Stack Exchange](https://i.stack.imgur.com/63YGS.png)