Document Type : Research Paper

Authors

1 Ph.D. Student, Department of Animal Sciences, University College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran

2 Associate Professor, Department of Animal Sciences, University College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran

3 Professor, Department of Animal Sciences, University College of Agriculture & Natural Resources, University of Tehran, Karaj, Iran

Abstract

The objective of this study was to compare six statistical methods for prediction of genomic breeding
values for traits with different genetic architecture in term of gene effects distributions and number of
Quantitative Traits Loci (QTLs). A genome consisted of 500 bi-allelic single nucleotide polymorphism
(SNP) markers distributed over a chromosomes with 100 cm length was simulated. Three different gene
effects distributions (uniform, normal and gamma) were considered. Number of QTLs varied from 50 to
200. Finally, nine quantitative traits with different genetic architecture were generated. The performance
of six statistical methods of genomic prediction that differ with respect to assumptions regarding
distribution of marker effects, including i) Genomic Best Linear Unbiased Prediction (GBLUP), ii) Ridge
Regression Best Linear Unbiased Prediction (RRBLUP), iii) Bayes A, iv) Bayes B, v) Bayes C, and vi)
Bayesian least absolute shrinkage and selection operator (Bayes L) are presented. The accuracy of
prediction declined significantly over generations (P< 0.05) but Bayesian methods outperformed GBLUP
and RRBLUP in persistence of accuracy of genomic estimated breeding values over generations.
Bayesian methods were superior to GBLUP and RRBLUP when the gene effects distribution generated
from gamma distribution. The highest accuracy of genomic breeding values was observed when the gene
effects come from normal distribution. In all statistical evaluation methods with increasing the number of
QTLs towards 200, the accuracy of predicted genomic values has been decreased. In general, Bayesian
and GBLUP methods performed better in prediction than RRBLUP method. These results gave some
evidences that when the genetic architecture of quantitative traits deviated from infinitesimal model
assumptions, Bayesian methods usually perform better than GBLUP and RR-BLUP.

Keywords

1 . Abdollahi-Arpanahi R, Pakdel A and Zandi-Baghchehmaryam MB (2012) From infinitesimal model to Genomic Selection. Modern Genetics. 17(2): 105-114 (in Persian).
2 . Bostan A, Nejati Javaremi A, Moradi Shahr Babak M and Saatchi M (2012) Using the dense molecular markers near the specific trait major genes for genomic prediction. Iranian Journal of Animal Science. 44(1): 53-60. (in Persian)
3 . Cole JB, VanRaden PM, O'Connell JR, Van Tassell CP, Sonstegard TS, Schnabel RD, Taylor JF and Wiggans GR (2009) Distribution and location of genetic effects for dairy traits. Dairy Science. 92(6): 2931-46.
4 . Colombani  C, Legarra  A, Fritz  S, Guillaume  F, Croiseau  P, Ducrocq  V and Robert-Granié C (2012) Application of Bayesian least absolute shrinkage and selection operator (LASSO) and BayesCp methods for genomic selection in French Holstein and Montbéliarde breeds. Dairy Science. 96: 575-591.
5 . Daetwyler HD, Calus MP, Pong-Wong R, De Los Campos G and Hickey JM (2013) Genomic prediction in animals and plants: simulation of data, validation, reporting, and benchmarking. Genetics. 193: 347-65.
6 . Daetwyler HD, Pong-Wong R, Villanueva B and Woolliams JA (2010) The impact of genetic architecture on genome-wide evaluation methods. Genetics. 185(3): 1021-31.
7 . De los Campos G, Gianola D and Rosa GJM (2009) Reproducing kernel Hilbert spaces regression: A general framework for genetic evaluation. Animal Science. 87: 1883-1887.
8 . De Los Campos G, Hickey JM, Pong-Wong R, Daetwyler HD and Calus MP (2013) Whole-genome regression and prediction methods applied to plant and animal breeding. Genetics. 193: 327-45.
9 . De los Campos G and Perez PR (2012) BGLR: Bayesian Generalized Linear Regression. R Package. http://bglr.r-forge.r-project.org/
10 . Gianola D, Fernando RL and Stella A (2006) Genomic-assisted prediction of genetic value with semiparametric procedures. Genetics. 173(3): 1761-76.
11 . Habier D, Fernando RL and Dekkers JC (2007) The impact of genetic relationship information on genome-assisted breeding values. Genetics. 177(4): 2389-2397.
12 . Habier D, Fernando RL, Kizilkaya K and Garrick DJ (2011) Extension of the Bayesian alphabet for genomic selection. BMC Bioinformatics. 12(1): 186.
13 . Hayes BJ, Pryce J, Chamberlain AJ, Bowman PJ and Goddard ME (2010) Genetic architecture of complex traits and accuracy of genomic prediction: coat color, milk-fat percentage, and type in Holstein cattle as contrasting model traits. PLOS Genetics. 6(9): 1001139.
14 . Hoerl AE and Kennard RW (1970) Ridge regression: Biased estimation for nonorthogonal problems. Technometrics. 12(1): 55-67.
15 . Meuwissen TH, Hayes BJ and Goddard ME (2001) Prediction of total genetic value using genome-wide dense marker maps. Genetics. 157(4): 1819-1829.
16 . Muir WM (2007) Comparison of genomic and traditional BLUP-estimated breeding value accuracy and selection response under alternative trait and genomic parameters. Animal Breeding and Genetics. 124: 342-355.
17 . Nejati-Javaremi A, Smith C and Gibson JP (1997) Effect of total allelic relationship on accuracy of evaluation and response to selection. Animal Science. 7(5): 1738-1745.
18 . Park T and Casella G (2008) The bayesian lasso. American Statistical Association. 103(482): 681-686.
19 . Resende MFR, Muñoz P, Resende MD, Garrick DJ, Fernando RL, Davis JM, Jokela EJ, Martin TA, Peter GF and Kirst M (2012) Accuracy of Genomic Selection Methods in a Standard Data Set of Loblolly Pine (Pinus taeda L.). Genetics. 190: 1503-1510.
20 . Schaeffer LR (2006) Strategy for applying genome-wide selection in dairy cattle. Journal of Animal Breeding and Genetics. 123: 218-223.
21 . Shirali M, Miraei-Ashtiani SR, Pakdel A, Haley C and Pong-Wong R( 2012) Comparison between Bayesc and GBLUP in Estimating Genomic Breeding Values under Different QTL Variance Distributions, in Abstract from ICQG2012 - 4th International Conference on Quantitative Genetics, . Edinburgh, United Kingdom. 261-268.
22 . Swami M (2010) Complex traits: Using genetic architecture to improve predictions. Nature Review Genetics. 11(11): 748.
23 . Technow FR (2011) Package hypred: Simulation of Genomic Data in Applied Genetics. University of Hohenheim.
24 . VanRaden PM (2008) Efficient Methods to Compute Genomic Predictions. Dairy Science. 91: 4414-4423.
25 . Wimmer V, Lehermeier C, Albrecht T, Auinger H-J, Wang Y, Schön C-C (2013) Genome-Wide Prediction of Traits with Different Genetic Architecture Through Efficient Variable Selection. Genetics. 195: 573-587.
26 . Wolc A, Arango J, Settar P, Fulton JE, O'Sullivan NP, Preisinger R, Habier D, Fernando R, Garrick DJ and Dekkers JC (2011) Persistence of accuracy of genomic estimated breeding values over generations in layer chickens. Genetics Selection Evolution. 43: 23.