Comparison on genomic predictions using three GBLUP methods and two single-step blending methods in the Nordic Holstein population

Genetics Selection Evolution

Research

Yuan Zhang¹  Ulrik S Nielsen²  Per Madsen³  Mogens S Lund³  Ole F Christensen³  Guosheng Su³  Hongding Gao⁴ 

[1] College of Animal Science and Technology, China Agricultural University, 100193, Beijing, People Republic of China;Danish Agricultural Advisory Service, DK-8200, Aarhus N, Denmark;Department of Molecular Biology and Genetics, Aarhus University, DK-8830, Tjele, Denmark;Department of Molecular Biology and Genetics, Aarhus University, DK-8830, Tjele, Denmark;College of Animal Science and Technology, China Agricultural University, 100193, Beijing, People Republic of China;

关键词: Single Nucleotide Polymorphism;    Relationship Matrix;    Genomic Prediction;    Estimate Breeding Value;    Genomic Estimate Breeding Value;   

DOI  :  10.1186/1297-9686-44-8

 received in 2011-10-28, accepted in 2012-03-28,  发布年份 2012

来源: Springer

【 摘 要 】

BackgroundA single-step blending approach allows genomic prediction using information of genotyped and non-genotyped animals simultaneously. However, the combined relationship matrix in a single-step method may need to be adjusted because marker-based and pedigree-based relationship matrices may not be on the same scale. The same may apply when a GBLUP model includes both genomic breeding values and residual polygenic effects. The objective of this study was to compare single-step blending methods and GBLUP methods with and without adjustment of the genomic relationship matrix for genomic prediction of 16 traits in the Nordic Holstein population.MethodsThe data consisted of de-regressed proofs (DRP) for 5 214 genotyped and 9 374 non-genotyped bulls. The bulls were divided into a training and a validation population by birth date, October 1, 2001. Five approaches for genomic prediction were used: 1) a simple GBLUP method, 2) a GBLUP method with a polygenic effect, 3) an adjusted GBLUP method with a polygenic effect, 4) a single-step blending method, and 5) an adjusted single-step blending method. In the adjusted GBLUP and single-step methods, the genomic relationship matrix was adjusted for the difference of scale between the genomic and the pedigree relationship matrices. A set of weights on the pedigree relationship matrix (ranging from 0.05 to 0.40) was used to build the combined relationship matrix in the single-step blending method and the GBLUP method with a polygenetic effect.ResultsAveraged over the 16 traits, reliabilities of genomic breeding values predicted using the GBLUP method with a polygenic effect (relative weight of 0.20) were 0.3% higher than reliabilities from the simple GBLUP method (without a polygenic effect). The adjusted single-step blending and original single-step blending methods (relative weight of 0.20) had average reliabilities that were 2.1% and 1.8% higher than the simple GBLUP method, respectively. In addition, the GBLUP method with a polygenic effect led to less bias of genomic predictions than the simple GBLUP method, and both single-step blending methods yielded less bias of predictions than all GBLUP methods.ConclusionsThe single-step blending method is an appealing approach for practical genomic prediction in dairy cattle. Genomic prediction from the single-step blending method can be improved by adjusting the scale of the genomic relationship matrix.

【 授权许可】

Unknown   
© Gao et al; licensee BioMed Central Ltd. 2012. This article is published under license to BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.