The dominant selective force acting on protein-coding regions throughout the human genome is purifying selection, which removes deleterious mutations. The fraction of substitutions that were positively selected, and can therefore be considered to be adaptive, can be estimated using methods based on comparisons of the relative amounts of change at two classes of sites sites which if changed produce amino acid changes and sites which if changed do not lead to amino acid changes. Current estimates find very low estimates of adaptive evolution in protein-coding regions during human evolution.
Keywords: purifying selection; adaptive evolution; human evolution; negative selection; positive selection




