Skip to main content
Identification of signatures of selection for intramuscular fat and backfat thickness in two Duroc populations
Journal of Animal Science
  • Eui-Soo Kim, Iowa State University
  • Roger Ros-Freixedes, Universitat de Lleida
  • Ramona N. Pena, Universitat de Lleida
  • Thomas J. Baas, Iowa State University
  • Joan Estany, University of Lleida
  • Max F. Rothschild, Iowa State University
Document Type
Publication Version
Published Version
Publication Date

Intramuscular fat (IMF) content is an important trait affecting the quality of pork. Two Duroc populations, one under positive selection for IMF and the other selected for decreased backfat but under stabilizing selection for IMF, were used to identify signatures of selection associated with IMF using 60,000 single-nucleotide polymorphism data. The effects of selection were analyzed between 2 lines or groups representing selected and control animals within each population using a discriminant analysis of principal components and Wright’s fixation index (FST). Moreover, extended haplotype homozygosity-based approaches were used to examine the changes in haplotype frequency due to recent selection. Each statistical method identified 10–20 selection signatures. A few haplotype-based signatures of selection agreed with results from a genome-wide association study (GWAS), while FST measures showed a better agreement with GWAS results. Agreement of marker-trait associations and signatures of selection was limited, and further examination will be necessary to understand the effect of selection on IMF and why some regions identified by GWAS did not appear to respond to the selection practiced. The genes in 21 consensus selection signatures were examined. Several genes with an effect on overall fatness were identified, but further research is needed to assess whether or not some of them could have a specific effect on IMF.


This is an article from Journal of Animal Science 93 (2015): 3292, doi:10.2527/jas.2015-8879. Posted with permission.

Copyright Owner
American Society of Animal Science
File Format
Citation Information
Eui-Soo Kim, Roger Ros-Freixedes, Ramona N. Pena, Thomas J. Baas, et al.. "Identification of signatures of selection for intramuscular fat and backfat thickness in two Duroc populations" Journal of Animal Science Vol. 93 Iss. 7 (2015) p. 3292- - 3302
Available at: