Post-GWAS mapping of genomic regions in quiescent chromatin linked to average feed intake per visit in Landrace pigs

In this study, we conducted a GWAS analysis to further investigate the genomic regions associated with average feed intake per visit (AFIV) in Landrace pigs. Three QTL regions, located on chromosomes 12, 13, and 14, were identified based on visualizations in the Integrative Genomics Viewer (IGV). To assess the functionality of these regions, significant SNPs were compared with publicly available ATAC-Seq data from relevant tissues, including muscle, liver, cerebral cortex, and adipose tissue. All regions associated with AFIV were found to be within the “E15” chromatin state, characterized as a quiescent region with low transcriptional activity. This association suggests a potential regulatory role for these regions, which may act during specific developmental stages or in particular tissues, despite their epigenetically silent state. Our findings underscore the complexity of genetic and epigenetic regulation of feeding behavior in pigs and provide valuable insights for genetic improvement strategies targeting feed efficiency in Landrace pigs. Future functional studies are needed to clarify the role of these quiescent regions in regulating feed intake, thereby contributing to advances in genetic selection. Moreover, this work aligns with the United Nations Sustainable Development Goals (SDGs), particularly SDG 2 (Zero Hunger and Sustainable Agriculture), by promoting progress in efficient and sustainable animal production, and SDG 12 (Responsible Consumption and Production), by contributing to the optimization of feed resource use in pig farming.