A polymorphism for a lethal phenotype governed by two duplicate genes in mimulus guttatus

Abstract

A polymorphism in a British population of Mimulus guttatus for an albino phenotype controlled by two duplicate genes is described. This polymorphism is shown to be allelic with one studied previously by Kiang and Libby (1972) in California. The polymorphism has remained stable between 1977 and 1991. Some substructuring of the population is evident, with the double heterozygote being the most frequent phenotype in the main stream flowing through the study site. The theoretical problems associated with the maintenance of a two locus polymorphism are discussed. © 1993 The Genetical Society of Great Britain.