Genetic variability and geographical structure in partially selfing populations

In order to clarify the effect of selfing on genetic variation in geographically structured populations, Wright's island model is generalized to include; the effects of extinction, mutation, selfing, and migration of pollen and seed. The equilibrium probabilities of identity by descent for two genes are obtained. It is found that selfing causes a decrease of the variation within colonies and an increase of the variation between colonies. Our model partly explains the "heterozygosity paradox" but other factors such as selection are necessary to fully account for the paradox.