Negative relationship between nucleotide sequence asymmetry and codon adaptation index (CAI) for 43 pairs of ohnologs in the S. cerevisiae genome. The sequence asymmetry measure on the x axis was calculated as the difference between unique nucleotide sites at the ancestral-like copy and the derived-like copy within an ohnolog pair. The y axis represents the difference in CAI values between the ancestral-like copy and the derived-like copy for the same ohnolog pair. There was a significant negative correlation between differences in rate asymmetry and CIA values for ohnologs (Kendall's tau = -0.453; p < 0.0001).
Bu et al. BMC Evolutionary Biology 2011 11:279 doi:10.1186/1471-2148-11-279