Genetic Variance in the F₂ Generation of Divergently Selected Parents

Abstract

Either by selective breeding for population divergence or by using natural population differences, F₂ and advanced generation hybrids can be developed with high variances. We relate the size of the genetic variance to the population divergence based on a forward and backward mutation model at a locus with two alleles with additive gene action. The effects of population size and initial gene frequency are also explored. Larger parental population sizes increase the F₂ genetic variance if the initial probability distribution is uniform or U-shaped. However, population size has the opposite effect if the initial distribution of gene frequencies is skewed such as it would be with newly arriving alleles. These alleles contribute to the genetic variance sooner when the selection pressure is higher or when the effective population size is smaller.

Citation

Koshy, M.P.; Namkoong, G.; Roberds, J.H. 1998. Genetic Variance in the F₂ Generation of Divergently Selected Parents. Theor. Appl Genet (1998) 97:990-993