- THIS ARTICLE
- Full Text
- Full Text (PDF)
-
All Versions of this Article:
genetics.105.054197v1
173/4/2247 most recent - Alert me when this article is cited
- Alert me if a correction is posted
- SERVICES
- Email this article to a friend
- Similar articles in this journal
- Similar articles in PubMed
- Alert me to new issues of the journal
- Download to citation manager
- Reprints & Permissions
- CITING ARTICLES
- Citing Articles via Google Scholar
- GOOGLE SCHOLAR
- Articles by Gianola, D.
- Articles by Odegaard, J.
- Search for Related Content
- PUBMED
- PubMed Citation
- Articles by Gianola, D.
- Articles by Odegaard, J.
Originally published as Genetics Published Articles Ahead of Print on April 19, 2006.
Genetics, Vol. 173, 2247-2255, August 2006, Copyright © 2006
doi:10.1534/genetics.105.054197
On the Quantitative Genetics of Mixture Characters
Daniel Gianola*,
,1,
Bjorg Heringstad
and
Jorgen Odegaard
* Department of Animal Sciences, University of Wisconsin, Madison, Wisconsin 53706 and
Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, N-1432 Ås, Norway
1 Corresponding author: Department of Animal Sciences, 1675 Observatory Dr., Madison, WI 53706.
E-mail: gianola{at}calshp.cals.wisc.edu
Finite mixture models are helpful for uncovering heterogeneity due to hidden structure. Quantitative genetics issues of continuous characters having a finite mixture of Gaussian components as statistical distribution are explored in this article. The partition of variance in a mixture, the covariance between relatives under the supposition of an additive genetic model, and the offspringparent regression are derived. Formulas for assessing the effect of mass selection operating on a mixture are given. Expressions for the genetic and phenotypic correlations between mixture and Gaussian traits and between two mixture traits are presented. It is found that, if there is heterogeneity in a population at the genetic or environmental level, then genetic parameters based on theory treating distributions as homogeneous can lead to misleading interpretations. Some peculiarities of mixture characters are: heritability depends on the mean values of the component distributions, the offspringparent regression is nonlinear, and genetic or phenotypic correlations cannot be interpreted devoid of the mixture proportions and of the parameters of the distributions mixed.