Mapping the Bovine Genome


The bovine genome sequence contains the markers for important genes that assist in improving genetic evaluation systems. Knowing the genome will enable researchers to measure feed efficiency, reproductive traits and animal health much more easily.

According to Ronnie Green, U.S. Department of Agriculture (USDA) Agriculture Research Services (ARS), researchers are working to develop road maps of each chromosome. Green made his comments in Lexington, Ky., May 29 at the Emerging Technologies roundtable discussion of the 35th annual meeting of the Beef Improvement Federation (BIF).

Researchers use these road maps to identify chromosomal areas called quantitative trait loci (QTL), Green explained. After a QTL is identified, the next step is to identify what trait it actually represents. Gene markers and animals are used to refine the location of the QTL. Gene markers have already been found for traits such as tenderness and marbling, but much of the genome is still being studied.

Green defined a few terms to help producers understand the genetic infrastructure:
• A gene is the functional and physical unit of heredity that is passed from parent to offspring.
• A genome is the DNA comprising the complete genetic complement of an organism.
• The word genomics was developed in 1986, and is a new scientific discipline of mapping gene sequencing and analyzing genomes. There are two basic categories of genomics. Structural genomics describes the physical structure of the genetic material. Functional genomics are used to improve genetics and performance in animals after the structure has been mapped.

Currently, Green is soliciting funds for the bovine genome research. He said that approximately $51 million is needed to map the genome. Half of the money is coming from the National Human Genome Research Institute (NHGRI) if the agriculture sector raises the other half. Green is currently in negotiations with several groups to raise the money, including the state of Texas, several international countries, Genome Canada, USDA-ARS and National Cattlemen’s Beef Association (NCBA).

Green said there are several benefits to sequencing the cow genome. These include improving the comparative map, reducing time and costs to identify genes, collaborating with human health research, and placement in the public domain.

— by Stephanie Veldman