The relationship between sequence divergence and the proportion of human gene pairs with diverged expression. (A) Synonymous divergence (K_S) is used to represent sequence divergence. Each point represents 30 gene pairs. (B) Nonsynonymous divergence (K_A) is used to represent sequence divergence. Each point represents 60 gene pairs. Solid diamonds represent the proportion of gene pairs with diverged expression in at least one tissue, and open diamonds represent proportion of gene pairs with diverged expression in at least two tissues. Solid and punctured lines are the corresponding linear regressions.