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Marker research offers broad benefits for Canadian beef producers, industry and consumers, says Dr. Randall Weselake.

Advancing technology and a growing knowledge base are making "molecular markers" an exciting new tool in beef science - one that promises major benefits for Canadian beef producers, industry and consumers.

"Markers are essentially 'molecular fingerprints' that make it easier for researchers to identify valuable genetic traits, such as high marbling potential," explains Dr. Randall Weselake of the University of Lethbridge, one of a handful of beef researchers pioneering the technology in Canada.

There is broad potential to develop molecular markers for everything from marbling to tenderness and growth potential, he says. Progress in each area would make it easier for the beef industry to identify and select young animals likely to express those desired traits.

"Marker work and related beef genomics work is especially important now in light of the BSE situation," says Weselake. "This research can lead to benefits that reinforce the image of beef as a safe, high quality food product. It could also have applications to improve our understanding of BSE."

Weselake and colleagues explored the potential of genetic and biochemical markers for beef marbling, in a study funded in part by the Canada Alberta Beef Industry Development Fund (CABIDF). Here, he comments on the technology and the promise it holds.

A. The idea is that by developing a marker for a specific trait, such as marbling, you can greatly improve animal selection. For example, you could take a sample from a younger animal, through a biopsy or similar method, and run a genetic test to get an idea of whether or not that animal will eventually show that trait. The markers would serve as tools to assist breeders and producers in selecting animals with specific traits. They can then increase the population of animals with a desired trait, or make decisions for use of an animal when that animal is at an earlier age.

A. This work would not have been possible even a few years ago, because we didn't have the required molecular genetic tools at that time. The required analytical tools and the whole knowledge base behind our understanding of molecular biology work was simply not available. Although the sophistication of the techniques has a lot to do with it, one of the main requirements is our own basic knowledge of the biological processes - in this case, our knowledge of the processes behind fat formation.

A. Marker research is an important field not only in animal science but in biology in general. As we pursue this area, we're advancing fundamental knowledge of the physiology and biochemistry of fat formation, which may apply to other species. There could be spin-offs in human medical research and other areas, so we have to keep our eyes open for these other applications.

A. One example closely related to our work is activity at the University of Alberta, where researchers are working on improving carcass traits.

The U of A researchers have taken a stricter molecular biology approach than we have, focusing on the association between DNA patterns and the marbling trait. We've focused at another level, examining the actual enzyme activities that are associated with marbling and with specific characteristics of the marbling fat.

We've done some genetic work as well, but in a different vein. Our genetic work has focused on something known as "transcript," which is a mobile form of genetic material. Information in the cell nucleus is eventually converted into a type of enzyme that does a job. This enzyme contains something known as messenger RNA, or transcript, which is a mobile form of the genetic information from the nucleus.

In our CABIDF marbling study, what we have examined is a process of gene expression, with the ultimate end point of that gene expression taking the form of enzyme activity affecting fat. We're looking at the biochemistry, plus the relationship between that biochemistry and the genetic material, but not specifically focusing on the DNA.

A. Our marbling study is good example. We were able to identify some potential genetic markers to help the beef industry identify and select animals at a young age that will produce highly-marbled beef. Also, one of the potential markers we identified is oleic acid, which is a fatty acid known to reduce cholesterol in humans.

Both of these results are key steps toward increasing the market value of Canadian beef. Consumers are recognizing the value of well-marbled beef, and markers will help improve this trait in Canadian herds. The oleic acid finding is a spin-off benefit of the study that may enhance the consumer perception of beef as a healthy food product.

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