Relative strength of selective pressure on RecQ helicases and their partners. The number of nonsynonymous (amino acid altering) nucleotide substitutions per nonsynonymous sites (dN) plotted against the number of synonymous nucleotide substitutions per synonymous sites (dS) are plotted for RecQ genes and their partners. The dashed line indicates the neutral expectations (i.e., dN = dS); values below the dashed line indicate purifying selection is in operation, as reflected by dS > dN.
Piontkivska et al. BMC Genomics 2009 10:189 doi:10.1186/1471-2164-10-189