Advertisement

Springer Nature is making Coronavirus research free. View research | View latest news | Sign up for updates

Equilibria under natural selection at a sex-linked locus

  • 40 Accesses

  • 34 Citations

Summary

An equilibrium of a pair of allelomorphs at a sex-linked locus can be stable under natural selection if the fitnesses of the mutant hemizygote and homozygote differ from that of the normal in opposite directions, even if the female heterozygote is less fit than the mean of the homozygotes. But if the fitnesses of the mutant homozygote and liemizygote differ in the same direction from those of the normals, stability demands that the heterozygous female should be fitter than either homozygote. The facts as to human glucose-6-phosphate dehydrogenase are discussed in the light of these findings. In this case it seems likely that there is real heterosis, but this may not be true for most such equilibria found in nature.

This is a preview of subscription content, log in to check access.

References

  1. Bennett, H. H. (1958). The existence and stability of selectively balanced polymorphism at a sex-linked locus.Aust. J. Bio. Sci.,11, 598–602.

  2. Haldane, J. B. S. (1926). A mathematical theory of natural and artificial selection, Part III.Proc. Comb. Phil. Soc.,23, 363–372.

  3. Haldane, J. B. S. (1937). The effect of variation on fitness.Amer. Nat.,71, 337–349.

  4. Haldane, J. B. S. And Jayakar, S. D. (1962). An enumeration of human relationships.J. Genet.,58, 81–107.

  5. Mandel, S. P. H. (1959). Stable equilibrium at a sex-linked locus.Nature,183, 1347–1348.

  6. Meera Khan, P. (1964), Glucosc-6-Phosphate Dehydrogenase deficiency in an Indian rural area.J. Genet.,59, 14–48.

  7. Motulsky, A. (1963). Genetic systems involved in disease susceptibility in mammals-inGenetic Selection in Man. Univ. Mich. Press: Ann Arbor.

  8. Reed, T. E. And Neel, J. V. (1959). Huntington’s chorea in Michigan, II. Selection and mutation.Am. J. Hum. Gen.,11, 107–136.

  9. Schull, W. J. (1963).Genetic selection in man. Univ. Mich. Press: Ann Arbor.

  10. Sprott, D. A. (1957). The stability of a sex-linked allelic system.Ann. Hum. Gen.,22, 1–6.

Download references

Author information

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Haldane, J.B.S., Jayakar, S.D. Equilibria under natural selection at a sex-linked locus. J Genet 59, 29 (1964). https://doi.org/10.1007/BF02984134

Download citation

Keywords

  • Malaria
  • Stable Equilibrium
  • Dehydrogenase Deficiency
  • Heterozygous Female
  • Malarial Region