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The mutational load of a multigene family with uniform members

Published online by Cambridge University Press:  14 April 2009

Tomoko Ohta
Tomoko Ohta
Affiliation:
National Institute of Genetics, Mishima 411, Japan
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The mutational load of a multigene family with uniform members was studied by computer simulations. Two models of selection, truncation and exponential fitness, were examined, by using a simple model of gene conversion. It was found that the load is much smaller than the Haldane–Muller prediction under the truncation selection, and that it becomes approximately equal to the value calculated by the formula, nv(1 − q)/(m − nq), where n is the copy number, v is the rate of detrimental mutation per gene copy, m is the truncation point in terms of the number of detrimental genes eliminated, and q is the equilibrium frequency of detrimental mutation. However the equilibrium frequency cannot be analytically obtained. For the exponential fitness model, the load is close to the Haldane–Muller value. When there is no gene conversion, the load becomes larger than the cases with conversion both for the truncation and the exponential fitness models. Thus, gene conversion or other mechanisms that are responsible for contraction–expansion of mutants on chromosomes helps eliminating deleterious mutations occurring in multigene families.

Type
Research Article
Information
Genetics Research , Volume 53 , Issue 2 , April 1989 , pp. 141 - 145
Copyright
Copyright © Cambridge University Press 1989

References

Arnheim, N. (1983). Concerted evolution of multigene families. In Evolution of Genes and Proteins (ed. Nei, M. and Koehn, R. K.), pp. 38–61. Sunderland, Mass.: Sinauer.Google Scholar
Dover, G. A. (1982). Molecular drive: a cohesive mode of species evolution. Nature 299, 111–117.CrossRefGoogle ScholarPubMed
Fedoroff, N. V. (1979). On spacers. Cell 16, 697–710.CrossRefGoogle ScholarPubMed
Haldane, J. B. S. (1937). The effect of variation on fitness. American Naturalist 71, 337–349.CrossRefGoogle Scholar
Haldane, J. B. S. (1957). The cost of natural selection. Journal of Genetics 55, 511–524.CrossRefGoogle Scholar
Hood, L., Campbell, J. H. & Elgin, S. C. R. (1975). The organization, expression, and evolution of antibody genes and other multigene families. Annual Review of Genetics 9, 305–353.CrossRefGoogle ScholarPubMed
Kaplan, N. L. & Hudson, R. R. (1987). On the divergence of genes in a multigene family. Theoretical Population Biology 31, 178–194.CrossRefGoogle Scholar
Kimura, M. & Maruyama, T. (1966). The mutational load with epistatic gene interactions in fitness. Genetics 54, 1337–1351.CrossRefGoogle ScholarPubMed
King, J. L. (1966). The gene interaction component of the genetic load. Genetics 53, 403–413.CrossRefGoogle ScholarPubMed
Kondrashov, A. S. & Crow, J. F. (1988). King's formula for the mutation load with epistasis. Genetics (in the press).CrossRefGoogle ScholarPubMed
Matsuo, Y. & Yamazaki, T. (1988). Nucleotide variation and divergence in the histone multigene family in Drosophila melanogaster. Genetics (in the press).Google Scholar
Muller, H. J. (1950). Our load of mutations. American Journal of Human Genetics 2, 111–176.Google ScholarPubMed
Nagylaki, T. (1984 a). The evolution of multigene families under intrachromosomal gene conversion. Genetics 106, 529–548.CrossRefGoogle ScholarPubMed
Nagylaki, T. (1984 b). Evolution of multigene families under interchromosomal gene conversion. Proceedings of the National Academy of Sciences, USA 81, 3796–3800.CrossRefGoogle ScholarPubMed
Ohta, T. (1980). Evolution and Variation of Multigene Families. Lecture Notes in Biomathematics, vol. 37. Berlin, New York: Springer-Verlag.CrossRefGoogle Scholar
Ohta, T. (1982). Allelic and nonallelic homology of a supergene family. Proceedings of the National Academy of Sciences, USA 79, 3251–3254.CrossRefGoogle ScholarPubMed
Ohta, T. (1983 a). On the evolution of multigene families. Theoretical Population Biology 23, 216–240.CrossRefGoogle ScholarPubMed
Ohta, T. (1983 b). Time until fixation of a mutant belonging to a multigene family. Genetical Research 41, 47–55.CrossRefGoogle Scholar
Ohta, T. & Dover, G. A. (1984). The cohesive population genetics of molecular drive. Genetics 108, 501–521.CrossRefGoogle ScholarPubMed
Seperack, P., Slatkin, M. & Arnheim, N. (1988). Linkage disequilibrium in human ribosomal genes: implications for multigene family evolution. Genetics 119, 943–949.CrossRefGoogle ScholarPubMed