I am writing a paper, and I want to refer to the original paper that coined the term dN/dS (or Ka/Ks for that matter). I have found early works on dN and dS (like Miyata and Yasunaga 1980), but cannot find the first paper that used the ratio dN/dS. Does anyone know which paper is the best to cite dN/dS?
Edit: dN is the rate of non-synonymous substitutions per non-synonymous sites; dS is the rate of synonymous substitutions per synonymous sites. dN/dS is simply the ratio between dN and dS.
Reference: Miyata, T., & Yasunaga, T. (1980). Molecular evolution of mRNA: A method for estimating evolutionary rates of synonymous and amino acid substitutions from homologous nucleotide sequences and its application. Journal of Molecular Evolution, 16(1), 23–36. https://doi.org/10.1007/BF01732067