In December 2003 USDA announced the launch of the sequencing of the bovine genome. Ronnie Green, USDA ARS, said that on Sept. 27 the first draft from the project will be released with the final report expected in about a year.

Click here to listen to the presentation

You will need Windows Media Player to listen in.
Click here to download a free version.

What's new in genetic technology?

Quantitative animal breeding and genetic research have been conducted on cattle for more than 75 years. In 1986 genomics was the term coined for the new scientific discipline of mapping, sequencing and analyzing genomes.

Ronnie Green of the U.S. Department of Agriculture (USDA), told more than 300 attendees at the 2004 National Angus Conference in Roanoke, Va., "The current tools (EPDs, performance records, etc.) you have available as breeders to make genetic improvement are always going to be the center of what you do," said Ronnie Green, national program leader for USDA Agricultural Research Service (ARS). "DNA and other technology is just going to add to those tools, not replace them."

The mammalian genome is made up of more than 3 billion pieces of information, Green said.

The first step of genomic research is to develop road maps of each chromosome — genetic linkage maps. In 1994 the first cattle linkage map was published both in Australia and the United States. Green said at that time there were less than 500 markers; today, there are more than 9,000.

After the development of a linkage map, chromosomal regions that are important to economically relevant traits (ERTs) can then be identified through a process known as "fine mapping." These regions are known as quantitative trait loci (QTL).

What has this mapping brought us? Some of the current tests available in the industry are:
• Thyroglobulin — marbling (GeneStar Marbling)
• Calpastatin — tenderness (GeneStar Tenderness)
• Calpain — tenderness
• Leptin — fat deposition
• Diacylglycerol acetyltransferase (DGAT) — fat deposition in milk
• Somatostatin — marbling
• ROCR (Marbling) — Australia CSIRO

So far, development of gene marker tests has focused on identifying the presence of genes that influence production traits and, particularly, carcass characteristics. However, Green predicted a shift in focus to create tests for genes affecting input traits, such as reproductive rate and disease resistance. Also in the future, the technology will likely be adapted to individual animal ID systems.

Green advised breeders to be practical. While many gene marker tests may become available, breeders will have to decide which tests offer the most benefit and are sustainable in terms of cost.

— by Troy Smith and Angie Stump Denton