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Figure 11 | BMC Evolutionary Biology

Figure 11

From: Conservation of pregnancy-specific glycoprotein (PSG) N domains following independent expansions of the gene families in rodents and primates

Figure 11

Nonsynonymous versus synonymous substitution rates for pairwise comparisons between N domains. The number of nonsynonymous substitutions per nonsynonymous site (dn) and the number of synonymous substitutions per synonymous site (ds) was calculated using the method of Yang and Neilson [46] for pairwise nucleotide comparisons. The N1, N2 and N3 domains of mouse PSGs (mN1, mN2 and mN3, respectively), the N1 domain of rat PSGs (rN1) and the N domain of human PSGs (hN) comprised individual data sets that were analysed in the following comparisons: mN1 vs mN2; mN1 vs mN3; mN2 vs mN3; mN1 vs rN1; mN1 vs hN. (A) Plot of d n against d s where each data point represents a pairwise comparison of a nucleotide sequence taken from each set under comparison. The 45° line of equivalence is drawn where d n = d s . (B) Box and whisker plot of d n /d s calculated from the pairwise comparisons of all sequences in one dataset against all sequences in the other dataset. Significant differences of p < 0.0001 (calculated by the Mann-Whitney method) were observed between all comparisons except intra-mouse comparisons.

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