Application of Molecular Genetics in Swine Production

North Carolina State University Swine Genetics Research from 2004-2005. Improvements in product quality, production efficiency, and health are key to the continued success of pork production in the United States. Genetic progress is made primarily through intense selection within specialized nucleus populations and purebred Duroc, Hampshire, Landrace, and Yorkshire pigs are the foundation for most nucleus populations. Genomic tools are expected to play a pivotal role in improving efficiency of pork production through genetic selection, however, most genomic tools currently available have been optimized for use in crossbred, not purebred, populations. In many cases these crossbred resource populations include breeds of pigs not currently being used by the US pork industry. Genetic markers have been made publicly available; however, application of these markers in purebred industry populations has been limited.


What Has Been Done:


A study was conducted at NCSU to illustrate our ability to identify genetic markers, specifically, single nucleotide polymorphisms (SNPs), which are informative in purebred Yorkshire, Landrace, Duroc, and Hampshire pigs. Regions of seven genes were studied in eight boars from the National Swine Registry panel. Each breed was represented by at least one animal; 2 Duroc, 1 Hampshire, 3 and 2 Yorkshire animals were selected for the preliminary study. Regions of each of the seven genes were sequenced in the eight animals to identify sequence differences (SNPs) within breed and across the breeds. A total of 18 SNPs were identified in the seven genes, ranging from 0 to 8 SNPs identified in each gene. Each of the SNPs was examined to determine which were potentially useful within each breed. In this pilot study, 10 of the 18 polymorphisms are informative in the Landrace breed, 6 in Hampshire, 4 in Duroc, and 3 in the Yorkshire breed.




The identification of DNA markers that are useful in purebred industry populations is necessary before genomic tools can be applied to commercial populations. SNPs have been identified in crossbred populations but have not been evaluated in purebred populations. Evaluation of these SNPs in purebred populations will transfer the research findings to commercial pig populations and aid the US pork industry in successfully improving economically important traits.