Variance and covariances of the numbers of synonymous and nonsynonymous substitutions per site.
Nei and Gojobori (1986) developed a simple method to estimate the numbers of synonymous (ds) and nonsynonymous (dN) substitutions per site. In the present paper, we have developed a method for computing variances and covariances of ds's and dN's and of the proportions of synonymous (ps) and nonsynonymous (pN) differences. We also have developed a method for computing the variances of mean dS, dN, pS, pN, without constructing a phylogenetic tree of the genes. We have conducted computer simulations based on simple evolutionary models and have shown that the new method gives good estimates of variances and covariances.
Ota
T
T
Institute of Molecular Evolutionary Genetics, Pennsylvania State University, University Park 16802.
Nei
M
M
D003198:Computer Simulation; D008957:Models, Genetic; D009154:Mutation; D012641:Selection, Genetic