Effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm model

<p>Abstract</p> <p>Covariance functions have been proposed to predict breeding values and genetic (co)variances as a function of phenotypic within herd-year averages (environmental parameters) to include genotype by environment interaction. The objective of this paper was to invest...

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Main Authors: Veerkamp Roel F, Bijma Piter, Calus Mario PL
Format: Article
Language:deu
Published: BMC 2004-09-01
Series:Genetics Selection Evolution
Subjects:
Online Access:http://www.gsejournal.org/content/36/5/489
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author Veerkamp Roel F
Bijma Piter
Calus Mario PL
author_facet Veerkamp Roel F
Bijma Piter
Calus Mario PL
author_sort Veerkamp Roel F
collection DOAJ
description <p>Abstract</p> <p>Covariance functions have been proposed to predict breeding values and genetic (co)variances as a function of phenotypic within herd-year averages (environmental parameters) to include genotype by environment interaction. The objective of this paper was to investigate the influence of definition of environmental parameters and non-random use of sires on expected breeding values and estimated genetic variances across environments. Breeding values were simulated as a linear function of simulated herd effects. The definition of environmental parameters hardly influenced the results. In situations with random use of sires, estimated genetic correlations between the trait expressed in different environments were 0.93, 0.93 and 0.97 while simulated at 0.89 and estimated genetic variances deviated up to 30% from the simulated values. Non random use of sires, poor genetic connectedness and small herd size had a large impact on the estimated covariance functions, expected breeding values and calculated environmental parameters. Estimated genetic correlations between a trait expressed in different environments were biased upwards and breeding values were more biased when genetic connectedness became poorer and herd composition more diverse. The best possible solution at this stage is to use environmental parameters combining large numbers of animals per herd, while losing some information on genotype by environment interaction in the data.</p>
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spelling doaj.art-a4070c0bdbd64efcaca247208e4a050a2022-12-21T21:17:07ZdeuBMCGenetics Selection Evolution0999-193X1297-96862004-09-0136548950710.1186/1297-9686-36-5-489Effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm modelVeerkamp Roel FBijma PiterCalus Mario PL<p>Abstract</p> <p>Covariance functions have been proposed to predict breeding values and genetic (co)variances as a function of phenotypic within herd-year averages (environmental parameters) to include genotype by environment interaction. The objective of this paper was to investigate the influence of definition of environmental parameters and non-random use of sires on expected breeding values and estimated genetic variances across environments. Breeding values were simulated as a linear function of simulated herd effects. The definition of environmental parameters hardly influenced the results. In situations with random use of sires, estimated genetic correlations between the trait expressed in different environments were 0.93, 0.93 and 0.97 while simulated at 0.89 and estimated genetic variances deviated up to 30% from the simulated values. Non random use of sires, poor genetic connectedness and small herd size had a large impact on the estimated covariance functions, expected breeding values and calculated environmental parameters. Estimated genetic correlations between a trait expressed in different environments were biased upwards and breeding values were more biased when genetic connectedness became poorer and herd composition more diverse. The best possible solution at this stage is to use environmental parameters combining large numbers of animals per herd, while losing some information on genotype by environment interaction in the data.</p>http://www.gsejournal.org/content/36/5/489environmental sensitivitygenotype by environment interactioncovariance functionenvironmental parameter
spellingShingle Veerkamp Roel F
Bijma Piter
Calus Mario PL
Effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm model
Genetics Selection Evolution
environmental sensitivity
genotype by environment interaction
covariance function
environmental parameter
title Effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm model
title_full Effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm model
title_fullStr Effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm model
title_full_unstemmed Effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm model
title_short Effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm model
title_sort effects of data structure on the estimation of covariance functions to describe genotype by environment interactions in a reaction norm model
topic environmental sensitivity
genotype by environment interaction
covariance function
environmental parameter
url http://www.gsejournal.org/content/36/5/489
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AT bijmapiter effectsofdatastructureontheestimationofcovariancefunctionstodescribegenotypebyenvironmentinteractionsinareactionnormmodel
AT calusmariopl effectsofdatastructureontheestimationofcovariancefunctionstodescribegenotypebyenvironmentinteractionsinareactionnormmodel