Multiple Genes Related to Muscle Identified through a Joint Analysis of a Two-stage Genome-wide Association Study for Racing Performance of 1,156 Thoroughbreds.
Thoroughbred, a relatively recent horse breed, is best known for its use in horse racing. Although myostatin (MSTN) variants have been reported to be highly associated with horse racing performance, the trait is more likely to be polygenic in nature. The purpose of this study was to identify genetic variants strongly associated with racing performance by using estimated breeding value (EBV) for race time as a phenotype. We conducted a two-stage genome-wide association study to search for genetic variants associated with the EBV. In the first stage of genome-wide association study, a relatively large number of markers (~54,000 single-nucleotide polymorphisms, SNPs) were evaluated in a small number of samples (240 horses). In the second stage, a relatively small number of markers identified to have large effects (170 SNPs) were evaluated in a much larger number of samples (1,156 horses). We also validated the SNPs related to MSTN known to have large effects on racing performance and found significant associations in the stage two analysis, but not in stage one. We identified 28 significant SNPs related to 17 genes. Among these, six genes have a function related to myogenesis and five genes are involved in muscle maintenance. To our knowledge, these genes are newly reported for the genetic association with racing performance of Thoroughbreds. It complements a recent horse genome-wide association studies of racing performance that identified other SNPs and genes as the most significant variants. These results will help to expand our knowledge of the polygenic nature of racing performance in Thoroughbreds.
Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Korea.
Dong-Hyun
DH
Shin
Horse Industry Research Center, Korea Racing Authority (KRA), Gwacheon 427-711, Korea .
Jin Woo
JW
Lee
Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Korea.
Jong-Eun
JE
Park
Genome Analysis Center, National Instrumentation and Environmental Management (NICEM), Seoul National University, Seoul 151-921, Korea .
Ik-Young
IY
Choi
Department of Statistics, Seoul National University, Seoul 151-747, Korea .
Hee-Seok
HS
Oh
C&K Genomics, Seoul 151-742, Korea .
Hyeon Jeong
HJ
Kim
Department of Agricultural Biotechnology, Animal Biotechnology Major, and Research Institute for Agriculture and Life Sciences, Seoul National University, Seoul 151-921, Korea ; C&K Genomics, Seoul 151-742, Korea .
Heebal
H
Kim
Estimated Breeding Value; Genome-wide Association Studies [GWAS]; Racing Performance; Single Nucleotide Polymorphism; Thoroughbred