Using a new technique, partial shotgun sequencing, researchers at the The Institute for Genomic Research and The Center for the Advancement of Genomics have produced a rough draft of the canine genome sequence.
The project, which was led by Ewen Kirkness, PhD, an investigator at the Institute for Genomic Research based in Rockville, Md., covers nearly 80 percent of the canine genome. The results of the study were published in the Sept. 26 issue of the journal Science. A male Standard Poodle was the source for the DNA that was used in the study.
On the basis of their analysis of the sequence and comparisons with the human and mouse genomes, the researchers found that the human and canine genomes are more similar than the human and mouse genomes, despite the fact that the dog was the first to diverge from the common ancestor shared by the three species. They also found dog gene equivalents for 75 percent of known human genes.
The technique Dr. Kirkness and his team used speeds up the sequencing process but may produce results that are less accurate than other sequencing techniques. Still, Dr. Kirkness and his colleagues argue that the new technique is a cost-effective and efficient way to sequence and analyze large eukaryotic genomes, now that there are several complete genomes available for comparison.
"In little more than a decade, genomics has advanced greatly, and we now have approximately 150 completed genomes, including the human, mouse, and fruit fly, in the public domain," said J. Craig Venter, PhD, the president of The Center for the Advancement of Genomics, in a statement.
"With each sequenced genome, the level of information gleaned through comparative genomics is invaluable to our understanding of human biology, evolution, and basic science research. Our new method is an efficient and effective way of sequencing that will allow more organisms to be analyzed while still providing significant information."
A more complete sequence of the canine genome may be available within several months. Researchers at the National Institutes of Health's National Human Genome Research Institute are working to sequence the canine genome, but are using a different technique that will provide greater coverage of the genome. That project, which is being led by Kerstin Lindblad-Toh, PhD, began in June of 2003 at the Whitehead/MIT Center for Genome Research in Cambridge, Mass., and should be finished within 12 months. The NIH researchers are using DNA from a Boxer.
According to the NIH, dog models have played an important role in advancing biomedical knowledge and techniques, including the development of bone marrow transplants. Additionally, dogs are prone to many of the same diseases—cancer, heart disease, and autoimmune disorders—that humans are. Research on the genetics of these diseases may yield new techniques to combat these diseases in both species, according to Francis S. Collins, MD, PhD, the director of the NIH's genome research institute.
"Once we are able to compare the dog genome with the human genome, the dog will likely prove to be man's best friend in more ways than ever imagined," Dr. Collins said in a statement.