Hostname: page-component-76fb5796d-vfjqv Total loading time: 0 Render date: 2024-04-27T21:15:34.733Z Has data issue: false hasContentIssue false
  • English
  • Français

Random selective advantages of genes and their probabilities of fixation*

Published online by Cambridge University Press:  14 April 2009

Louis Jensen
Louis Jensen
Affiliation:
Statistical Laboratory, Iowa State University, Ames, Iowa, U.S.A.
Rights & Permissions [Opens in a new window]

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 question of what is meant by random fluctuations in selection intensities in a finite population is re-examined. The model presented describes the change in the frequency of a gene in a haploid population of size M. It is assumed that in any generation the adaptive values of A and a are equally likely to be 1 + s: 1 or 1: 1 + s. If s is the selective advantage and x the frequency of gene A, then the first two moments of the change in frequency are found to be m(Δx) = x(1 − x)(1 − 2x) θ/2M and

where E(s2) = θ/M. The ultimate probability of fixation is computed, showing that variability in selection increases the chance of fixation of a rare gene. A more general form for m(Δx) also is obtained. This form is compared with the equation currently used in describing random fluctuations in selection intensities.

Type
Research Article
Information
Genetics Research , Volume 21 , Issue 3 , June 1973 , pp. 215 - 219
Copyright
Copyright © Cambridge University Press 1973

References

REFERENCES

Fisher, R. A. & Ford, E. B. (1947). The spread of a gene in natural conditions in a colony of the moth Panaxia dominula L.Heredity 1, 143–174.Google Scholar
Gillespie, J. (1973). Haploid alleles in uncorrelated environments. Genetical Research 21, 115–120.CrossRefGoogle Scholar
Jensen, L. & Pollak, E. (1969). Random selective advantages of a gene in a finite population. Journal of Applied Probability 6, 19–37.CrossRefGoogle Scholar
Kimura, M. (1962). On the probability of fixation of mutant genes in a population. Genetics 47, 713–719.CrossRefGoogle ScholarPubMed
Ohta, T. (1972). Fixation probability of a mutant influenced by random fluctuation of selection intensity. Genetical Research 19, 33–38.Google Scholar