Identifying SNPs associated with birth weight and days to 100 kg traits in Yorkshire pigs based on genotyping-by-sequencing

Birth weight (BW) and days to 100 kg (D100) are important economic traits that are both affected by polygenes. However, the genetic architecture of these quantitative traits is still elusive. Genotyping-by-sequencing (GBS) data containing a large number of single nucleotide polymorphisms (SNPs) have become a powerful tool in genomic analysis. To better understand their complex genetic structure, a total of 600 Yorkshire pigs were sequenced using GBS technology. After quality control, 279 787 SNPs were generated for subsequent genome-wide association study (GWAS). A total of 30 genome-wide SNPs (P<1.79E–07) were identified for D100. Furthermore, a total of 22 and 2 suggestive SNPs (P<3.57E–06) were detected for D100 and BW, respectively. Of these, one locus located on SSC12 (position: 46 226 512 bp) were evaluated to affect both BW and D100 in Yorkshire pigs, indicating the pleiotropism in different traits. Considering the function of candidate genes, two genes, NSRP1 and DOCK7, were suggested as the most promising candidate genes involved in growth traits. Thus, use of GBS is able to identify novel variants and potential candidate genes for BW and D100, and provide an opportunity for improving pig growth traits using genomic selection in pigs.