Human EP2 prostanoid receptors exhibit more constraints to mutations than human DP prostanoid receptors

Human D-type prostanoid (DP) and E-type prostanoid 2 (EP2) receptors are regarded as the most closely related receptors among prostanoid receptors. Although these receptors are generated by tandem duplication, their physiological outputs often oppose one another. In the present study, we extracted mutations occurring in the coding regions of both receptors using the 1000 genome project database and found that EP2 receptors have 8-fold fewer amino acid mutations. We speculate that EP2 receptors exhibit more constraints to mutations than DP receptors.