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Fixation time of overdominant alleles influenced by random fluctuation of selection intensity*

Published online by Cambridge University Press:  14 April 2009

Tomoko Ohta  and
Motoo Kimura
Tomoko Ohta
Affiliation:
National Institute of Genetics, Mishima, Japan
Motoo Kimura
Affiliation:
National Institute of Genetics, Mishima, Japan
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Summary

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It was demonstrated that the number of generations until fixation or loss of an overdominant alleles is influenced by random fluctuation of selection coefficients. When 2 < Vs, where is the mean selection coefficient against either homozygote and Vs is the between -generation variance of the selection coefficient, overdominance generally accelerates rather than retards fixation of segregating alleles. This finding should have important bearing on our consideration of the behaviour of polymorphic variants which are nearly neutral but have very slight overdominance. When the population size (Ne) is extremely large, not only Ne but also /Vs have to be considered in discussing the effectiveness of overdominance.

Type
Research Article
Information
Genetics Research , Volume 20 , Issue 1 , August 1972 , pp. 1 - 7
Copyright
Copyright © Cambridge University Press 1972

References

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