Expression divergence and protein sequence divergence. (A) Correlation between expression divergence and protein sequence divergence for human and opossum paralogs of different duplication ages and for 1:1 amniote and primate orthologs (Warnefors and Kaessmann 2013). Numbers of gene families within each group are shown above the bars. A single gene pair was sampled for each gene family and expression divergence was measured as Euclidean distances. (*) P < 0.02, (**) P < 0.001, (***) P < 0.00001, (NS) not significant. (B) Expression divergence (measured as Euclidean distances across all organs) and dN values for human duplicate genes of all duplication ages. Increasing bias toward expression divergence is indicated in shades of yellow and increasing bias toward protein divergence in blue. (C) Relationships among the five most overrepresented GO terms for ED-biased (orange) and dN-biased (blue) genes in each age category. Brighter colors correspond to young and lineage-specific duplication ages, darker colors to old and ancient duplication ages. Some intermediate terms were omitted for clarity.
