Hostname: page-component-7479d7b7d-767nl Total loading time: 0 Render date: 2024-07-13T16:39:58.826Z Has data issue: false hasContentIssue false
  • English
  • Français

The maintenance of the genetic variability of polygenic characters by heterozygous advantage

Published online by Cambridge University Press:  14 April 2009

M. G. Bulmer
M. G. Bulmer
Affiliation:
Department of Biomathematics, University of Oxford

Summary

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

The results of a previous paper on the effect of optimizing selection, mutation and drift on a metric character determined by a large number of loci have been extended to include the possibility that, in addition to selection for an optimal value, there may be independent selection in favour of heterozygotes; it is assumed for simplicity that at each locus the heterozygote has the same advantage, s, over each of the homozygotes. Under selection alone there is a stable equilibrium if s > ca2, where c is a measure of the intensity of the optimizing selection and a is the effect of a gene substitution. Under the additional forces exerted by mutation and by drift due to finite population size each locus behaves independently of the other loci as if it had a heterozygous advantage equal to (s − ca2).

Type
Research Article
Information
Genetics Research , Volume 22 , Issue 1 , August 1973 , pp. 9 - 12
Copyright
Copyright © Cambridge University Press 1973

References

REFERENCES

Bulmer, M. G. (1971). The stability of equilibria under selection. Heredity 27, 157–162.CrossRefGoogle ScholarPubMed
Bulmer, M. G. (1972). The genetic variability of polygenic characters under optimizing selection, mutation and drift. Genetical Research 19, 17–25.CrossRefGoogle ScholarPubMed
Bulmer, M. G. (1973). The maintenance of heterozygosity under the diffusion model. (In preparation.)Google Scholar
Kimura, M. (1964). Diffusion models in population genetics. Journal of Applied Probability 1, 177–232.CrossRefGoogle Scholar
Latter, B. D. H. (1970). Selection in finite populations with multiple alleles. II. Centripetal selection, mutation, and isoallelic variation. Genetics 66, 165–186.CrossRefGoogle ScholarPubMed
Robertson, A. (1962). Selection for heterozygotes in small populations. Genetics 47, 1291–1300.CrossRefGoogle ScholarPubMed
Wright, S. (1937). The distribution of gene frequencies in populations. Proceedings of the National Academy of Sciences, U.S.A. 23, 307–320.CrossRefGoogle ScholarPubMed