Rapid screening for phenotype - genotype associations by linear transformations of genomic evaluations

Background: Currently, association studies are analysed using statistical mixed models, with marker effects estimated by a linear transformation of genomic breeding values. The variances of marker effects are needed when performing the tests of association. However, approaches used to estimate the p...

Descripción completa

Guardado en:
Detalles Bibliográficos
Otros Autores: Gualdrón Duarte, José Luis, Cantet, Rodolfo Juan Carlos, Bates, Ronald O., Ernst, Catherine W., Raney, Nancy E., Steibel, Juan Pedro
Formato: Artículo
Lenguaje:Inglés
Materias:
Acceso en línea:http://ri.agro.uba.ar/files/download/articulo/2014gualdronduarte.pdf
LINK AL EDITOR
Aporte de:Registro referencial: Solicitar el recurso aquí
LEADER 04183cab a22003977a 4500
001 20250516163841.0
003 AR-BaUFA
005 20250801104040.0
008 250516t2014 xxud||||o|||| 00| b|eng d
999 |c 57261  |d 57261 
999 |d 57261 
999 |d 57261 
999 |d 57261 
999 |d 57261 
999 |d 57261 
999 |d 57261 
022 |a 1471-2105 
040 |a AR-BaUFA  |c AR-BaUFA 
245 0 0 |a Rapid screening for phenotype - genotype associations by linear transformations of genomic evaluations 
520 |a Background: Currently, association studies are analysed using statistical mixed models, with marker effects estimated by a linear transformation of genomic breeding values. The variances of marker effects are needed when performing the tests of association. However, approaches used to estimate the parameters rely on a prior variance or on a constant estimate of the additive variance. Alternatively, we propose a standardized test of association using the variance of each marker effect, which generally differ among each other. Random breeding values from a mixed model including fixed effects and a genomic covariance matrix are linearly transformed to estimate the marker effects. Results: The standardized test was neither conservative nor liberal with respect to type I error rate (false - positives), compared to a similar test using Predictor Error Variance, a method that was too conservative. Furthermore, genomic predictions are solved efficiently by the procedure, and the p-values are virtually identical to those calculated from tests for one marker effect at a time. Moreover, the standardized test reduces computing time and memory requirements. The following steps are used to locate genome segments displaying strong association. The marker with the highest − log(p-value) in each chromosome is selected, and the segment is expanded one Mb upstream and one Mb downstream of the marker. A genomic matrix is calculated using the information from those markers only, which is used as the variance-covariance of the segment effects in a model that also includes fixed effects and random genomic breeding values. The likelihood ratio is then calculated to test for the effect in every chromosome against a reduced model with fixed effects and genomic breeding values. In a case study with pigs, a significant segment from chromosome 6 explained 11% of total genetic variance. Conclusions: The standardized test of marker effects using their own variance helps in detecting specific genomic regions involved in the additive variance, and in reducing false positives. Moreover, genome scanning of candidate segments can be used in meta-analyses of genome-wide association studies, as it enables the detection of specific genome regions that affect an economically relevant trait when using multiple populations. 
650 |2 Agrovoc  |9 26 
653 |a GENOME WIDE ASSOCIATION 
653 |a MARKER VARIANCE 
653 |a PIG GENOTYPE 
700 1 |a Gualdrón Duarte, José Luis  |u Universidad de Buenos Aires. Facultad de Agronomía. Buenos Aires, Argentina.  |9 45707 
700 1 |a Cantet, Rodolfo Juan Carlos  |u Universidad de Buenos Aires. Facultad de Agronomía. Buenos Aires, Argentina.  |9 12817 
700 1 |a Bates, Ronald O.  |u Michigan State University. Department of Animal Science. East Lansing, MI, USA.  |9 67472 
700 1 |a Ernst, Catherine W.  |u Michigan State University. Department of Animal Science. East Lansing, MI, USA.  |9 73546 
700 1 |a Raney, Nancy E.  |u Michigan State University. Department of Animal Science. East Lansing, MI, USA.  |9 67474 
700 1 |a Steibel, Juan Pedro  |u Michigan State University. Department of Animal Science. East Lansing, MI, USA.  |u Michigan State University. Department of Fisheries and Wildlife. East Lansing, MI, USA.  |9 13048 
773 0 |t BMC Bioinformatics  |g Vol.15, no.7 (2014), art.246, grafs., tbls. 
856 |f 2014gualdronduarte  |i en internet  |q application/pdf  |u http://ri.agro.uba.ar/files/download/articulo/2014gualdronduarte.pdf  |x ARTI202505 
856 |u https://bmcbioinformatics.biomedcentral.com/  |z LINK AL EDITOR 
942 |c ARTICULO 
942 |c ENLINEA 
976 |a AAG