AMES, Iowa -- An Iowa State University experiment found the fatty acid composition of beef to be heritable, a fact that could help improve the healthfulness of beef.
Red meat consumption has decreased by 11 percent per person in the last twenty years, while poultry consumption increased 102 percent, according to the USDA’s Economic Research Service. One of the major factors affecting the decline in beef intake is due to the recommendation of dieticians and health professionals, cautioning against saturated fatty acids (SFA), which contribute to several vascular diseases. However, beef is a good source of iron, amino acids and B vitamins in the American diet.
Travis Knight, animal science assistant scientist, says that there is hope for consumers who have been told to stay away from SFA. "The fatty acid composition of beef could be improved by identifying and selecting for natural genetic differences that exist between animals," he says.
This experiment was done to determine the natural variability in beef fatty acid composition and to identify single nucleotide polymorphisms (SNPs) in the SCD gene, which is responsible for turning saturated fatty acids into monounsaturated fatty acids. An SNP is a single-pair change in the DNA structure that can act as a marker to associate fatty acid composition with a certain phenotype. The SCD gene is used because the genotyping of that gene is a useful tool for selection of heart-healthier beef cattle.
"The first step was to find out if the fatty acid composition is heritable and we found that it is. The second step was to find out why it is heritable, and we think we found an SNP that is associated with the fatty acid composition," Knight said. "Now that we found one SNP, we would like to find more."
Knight says the ultimate goal of the research is to develop DNA markers for use in selecting breeding stock to improve the fatty acid composition of beef, making for an even healthier food.
The research was conducted using the beef muscle of 800 sire-identified cattle originating from Iowa State University beef cattle breeding selection projects. Financial support for this experiment was provided be ISU Burroughs Endowment and by the Center for Designing Foods to Improve Nutrition.