RESEARCH AT ISU WORKING TO IMPROVE HEALTHFULNESS OF BEEF
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% per person in the last twenty years, while
poultry consumption increased 102%, 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.