Antagonistic pleiotropy and genetic polymorphism: A perspective

Abstract

Antagonistic pleiotropy, in which reproduction and viability counter each other, appears to be widely thought of great significance in life history theory and the evolution of senescence. However, the conditions for maintenance of polymorphism by antagonistic pleiotropy are quite restrictive. This is particularly so when there is no reversal of dominance for different traits, sex-limited expression of fitness components, finite population size or inbreeding. Furthermore, when antagonistic pleiotropy is compared with other mechanisms of balancing selection, it appears to have more restrictive conditions for the maintenance of polymorphism. Although these theoretical findings do not preclude the presence of loci that exhibit antagonistic pleiotropy, because it appears so unlikely that antagonistic pleiotropy is an important factor maintaining polymorphism, empirical evidence suggesting antagonistic pleiotropy as the factor maintaining polymorphism should be carefully scrutinized.