HOW MUCH HERITABLE VARIATION CAN BE MAINTAINED IN FINITE POPULATIONS BY MUTATION-SELECTION BALANCE?
- 1 December 1989
- Vol. 43 (8) , 1748-1766
- https://doi.org/10.1111/j.1558-5646.1989.tb02624.x
Abstract
The joint effects of stabilizing selection, mutation, recombination, and random drift on the genetic variability of a polygenic character in a finite population are investigated. A simulation study is performed to test the validity of various analytical predictions on the equilibrium genetic variance. A new formula for the expected equilibrium variance is derived that approximates the observed equilibrium variance very closely for all parameter combinations we have tested. The computer model simulates the continuum-of-alleles model of Crow and Kimura. However, it is completely stochastic in the sense that it models evolution as a Markov process and does not use any deterministic evolution equations. The theoretical results are compared with heritability estimates from laboratory and natural populations. Heritabilities ranging from 20% to 50%, as observed even in lab populations under a constant environment, can only be explained by a mutation-selection balance if the phenotypic character is neutral or the number of genes contributing to the trait is sufficiently high, typically several hundred, or if there are a few highly variable loci that influence quantitative traits.Keywords
Funding Information
- Austrian Fond zur Förderung der wissenschaftlich Forschung, Project (P5994)
This publication has 37 references indexed in Scilit:
- Quantitative genetic variability maintained by mutation-stabilizing selection balance in finite populationsGenetics Research, 1988
- Perturbations of positive semigroups and applications to population geneticsMathematische Zeitschrift, 1988
- Heritable variation and heterozygosity under a balance between mutations and stabilizing selectionGenetics Research, 1987
- The maintenance of polygenic variation through a balance between mutation and stabilizing selectionGenetics Research, 1986
- Inheritance of size and shape in a population of Darwin’s finches, Geospiza conirostrisProceedings of the Royal Society of London. B. Biological Sciences, 1983
- Genetic differentiation of quantitative characters between populations or species: I. Mutation and random genetic driftGenetics Research, 1982
- Population Variation in Continuously Varying Traits as an Ecological Genetics ProblemAmerican Zoologist, 1981
- Quantitative variation and gene numberNature, 1975
- Variation for metrical characters in Drosophila populations III. The nature of selectionHeredity, 1971
- Mutation and Quantitative VariationThe American Naturalist, 1955