TABLE 3

Substitution rates in melanocortin receptor genes

GeneNo. of codonsNonsynonymous rate (Ka)Synonymous rate (Ks)Ka:Ks ratio
MC1R3150.155 ± 0.08020.534 ± 0.08020.290
MC2R2960.061 ± 0.01400.630 ± 0.09690.096
MC3R3230.065 ± 0.01470.426 ± 0.07900.153
MC4R3320.040 ± 0.01110.487 ± 0.07620.081
MC5R3250.113 ± 0.02050.613 ± 0.09070.185

Rates are numbers of substitutions per site based on pairwise comparisons between rodent and human sequences. Sequences were obtained from GenBank. Accession numbers: mus musculus MC1R, X65635; human ACTHR, X65633; mus sp ACTHR, S78985; human MC3R, L06155; human MC4R, L08603; rattus norvegicus MC4R, U67863; human MC5R, L27080; and mus musculus MC5R, X76295.