through the combined use of this estimate and the number of nonsynonymous and synonymous substitutions per nucleotide site inferred from comparisons of entire human and rabbit hbbetamrna nucleotide sequences , we calculate ( a ) approximately 70 % of synonymous hbbeta mutations are adaptively undersirable and ( b ) the mutation rate underlying all changes is lesser than or equal to 10 ( -8 ) nucleotide substitutions per nucleotide site per year .
C0086418
human
C1415481
hbbeta