Farries, G. and Gough, K.F. and Parnell, Andrew and McGivney, B.A. and McGivney, C.L. and McGettigan, P.A. and MacHugh, D.E. and Katz, L.M. and Hill, E.W. (2019) Analysis of genetic variation contributing to measured speed in Thoroughbreds identifies genomic regions involved in the transcriptional response to exercise. Animal Genetics, 50. pp. 670-685. ISSN 0268-9146

Preview

Download (1MB) | Preview

Abstract

Despite strong selection for athletic traits in Thoroughbred horses, there is marked variation in speed and aptitude for racing performance within the breed. Using global positioning system monitoring during exercise training, we measured speed variables and temporal changes in speed with age to derive phenotypes for GWAS. The aim of the study was to test the hypothesis that genetic variation contributes to variation in end‐point physiological traits, in this case galloping speed measured during field exercise tests. Standardisation of field‐measured phenotypes was attempted by assessing horses exercised on the same gallop track and managed under similar conditions by a single trainer. PCA of six key speed indices captured 73.9% of the variation with principal component 1 (PC1). Verifying the utility of the phenotype, we observed that PC1 (median) in 2‐year‐old horses was significantly different among elite, non‐elite and unraced horses (P < 0.001) and the temporal change with age in PC1 varied among horses with different myostatin (MSTN) g.66493737C>T SNP genotypes. A GWAS for PC1 in 2‐year‐old horses (n = 122) identified four SNPs reaching the suggestive threshold for association (P < 4.80 × 10−5), defining a 1.09 Mb candidate region on ECA8 containing the myosin XVIIIB (MYO18B) gene. In a GWAS for temporal change in PC1 with age (n = 168), five SNPs reached the suggestive threshold for association and defined candidate regions on ECA2 and ECA11. Both regions contained genes that are significantly differentially expressed in equine skeletal muscle in response to acute exercise and training stimuli, including MYO18A. As MYO18A plays a regulatory role in the skeletal muscle response to exercise, the identified genomic variation proximal to the myosin family genes may be important for the regulation of the response to exercise and training.

Item Type:	Article
Additional Information:	Cite as: Farries, G., Gough, K.F., Parnell, A.C., McGivney, B.A., McGivney, C.L., McGettigan, P.A., MacHugh, D.E., Katz, L.M. and Hill, E.W. (2019), Analysis of genetic variation contributing to measured speed in Thoroughbreds identifies genomic regions involved in the transcriptional response to exercise. Anim Genet, 50: 670-685. https://doi.org/10.1111/age.12848
Keywords:	exercise; functional genomics; GWAS; global positioning system; horse; SNP; skeletal muscle;
Academic Unit:	Faculty of Science and Engineering > Research Institutes > Hamilton Institute Faculty of Science and Engineering > Mathematics and Statistics
Item ID:	14031
Identification Number:	https://doi.org/10.1111/age.12848
Depositing User:	Andrew Parnell
Date Deposited:	18 Feb 2021 16:01
Journal or Publication Title:	Animal Genetics
Publisher:	International Society for Animal Genetics
Refereed:	Yes
URI:	Publisher
Use Licence:	This item is available under a Creative Commons Attribution Non Commercial Share Alike Licence (CC BY-NC-SA). Details of this licence are available here

Repository Staff Only(login required)

Item control page

Downloads

Origin of downloads