On Thursday afternoon, the Beef Improvement Federation (BIF) Emerging Technology Committee conducted a discussion of the potential incorporation of DNA testing into practical cattle evaluation and genetic selection. Speaker Dick Quaas, Cornell University, stressed the need for validation of tests marketed commercially by genomic companies.
Quaas is a member of the BIF Molecular Technology Guidelines Committee charged with creating guidelines for standardized technology nomenclature, data collection and database entry, and incorporation of test information into breed improvement programs.
Quaas also serves on the National Beef Cattle Evaluation Consortium’s “project team” addressing commercialization of DNA testing technology.
“The Consortium team has a more narrow focus – development of a protocol for validation of gene marker tests. And the team will actually conduct the validation process,” explained Quaas. “Certainly, it is important to test the claims of marketing companies with independent data.”
Mark Thallman, USDA MARC
Also on the agenda was Mark Thallman, of the U.S. Meat Animal Research Center, discussing results of the Carcass Merit Project (CMP) driven by the National Cattlemen’s Beef Association and 13 breed associations. The beef checkoff-funded CMP’s objectives included development of procedures for collecting information necessary to develop expected progeny difference (EPD) values for carcass merit traits. Another objective was validation of DNA markers to be used in marker-assisted selection for improvement of carcass traits. Of particular interest is the development of selection tools for improving tenderness.
According to Thallman, the CMP validated previously discovered quantitative trait loci (QTL), or points in the DNA sequence, which are associated with carcass traits. The research sought to characterize 11 QTL to see which traits are affected by each QTL.
“Most QTL showed significant effects for more than one trait, but we are particularly excited about four of them,” said Thallman, referring to QTL associated with traits such as shear force, flavor, juiciness and overall tenderness, as well as marbling and ribeye area.
The experts agreed that this project brings the industry a step closer to potential DNA tests to help advance genes affecting carcass traits and particularly those that are hard to measure. However, they also agreed that it is too early to use the information as a seedstock marketing tool.
The most significant result of CMP, say the experts, is the sizable database of phenotypic information and DNA samples collected from a wide cross section of U.S. beef germplasm. The data and samples represent an unbiased resource population for use in validation of gene tests prior to marketing to cattle producers.
