earticle

영어

GWAS (Genome wide association study) strategy has been applied with the purpose to identity chromosomal regions and SNPs that control relevant traits. The development of SNP panel with the medium density (PorcineSNP60 BeadChip) allows the detection of QTL (Quantitative trait loci) and candidate genes near QTL with a higher resolution compared to using microsatellites in the past. The total number born (TNB) and the number of piglets weaned (NPW) are the most economical traits in pigs due to a huge impact on the efficiency of pig production. Therefore, the aim of this study was to detect regions (1-Mb windows) and SNPs associated with litter size (total number born, TNB) and the number of piglets weaned (NPW) for Yorkshire pigs. Reference population of 1,978 Yorkshire pigs were genotyped using Illumina Porcine SNP60 v2 SNP panel which were then imputed for missing genotypes with FImpute v2.2. BayesB with set to π (0.99) method was used to identify the informative window regions and deregressed EPD and their reliabilities were used as a response variable and a weighting factor in GWAS model. In total, 8 and 6 genome regions explaining over 0.75% of the genetic variance and 9 and 6 SNPs were identified for TNB and NPW traits, respectively. Those identified genome regions were located on SSC1, SSC6, SSC7, SSC11, SSC14 and SSC16 for TNB and SSC1, SSC4, SSC7 and SSC14 for NPW. No overlapping significant chromosome areas or QTL between TNB and NPW traits were detected. Our results suggested that it is feasible to improving the accuracy of the genomic selection by detecting QTLs for TNB and NPW traits.