This study aims to improve the understanding of the genetic mechanisms underlying backfat thickness (BFT) in pigs. We conducted a genome-wide association study (GWAS) using imputed genotype data and phenotype data on average backfat thickness at 100 kg (BFT_100) from 4,144 Yorkshire pigs, which identified 11 independent significant variants and prioritized 17 candidate genes. We then performed a transcriptome-wide association study (TWAS) and colocalization analysis by integrating the GWAS results with the Pig Genotype-Tissue Expression (PigGTEx) resources, identifying 27 TWAS-significant genes and 13 colocalized genes associated with BFT_100. Among these, two loci and three genes may be novel candidates for BFT_100. Our findings enhance the understanding of these key genes, especially FCN1, which may influence BFT_100 through altered expression in the gut and brain. These results provide valuable insights into the genetic architecture of BFT_100 and identify potential molecular markers that warrant future validation in pig breeding.

Read the full article in the Journal of Animal Science.