NEW YORK, Dec. 7 (GenomeWeb News) - Two studies published this month reveal genomic differences between dog breeds, as well as the complete dog genome.
An international team of researchers led by the Broad Institute published the genome sequence of the dog in the Dec. 8 issue of the journal Nature, the National Human Genome Research Institute said today.
The sequencing was largely funded by NHGRI as part of its Large-Scale Sequencing Research Network. The effort began in June 2003 and cost approximately $30 million.
The research effort also compared the human genome with the dog genome and discovered a common set of genetic elements -- roughly 5 percent of the human genome -- between the two mammals. Humans and dogs suffer from similar cancers, and understanding the genetic roots of disease in dogs will be significant for human cancers as well.
Researchers identified roughly 2.5 million SNPs sprinkled throughout the dog genome. Despite the physical diversity across dog breeds, they share large segments of DNA. Genetic tests and tools developed for any one breed will be useful to other breeds, the researchers said in a statement.
Comparison among dogs will help identify genes governing physical and behavioral differences, as well as the genetic underpinnings of disease, the statement said.
A separate study published by researchers at The Institute for Genomic Research in the December issue of Genome Research -- in a special issue devoted to dog genomes -- compared the genome sequences of a standard poodle and a boxer.
After identifying key genetic differences, the researchers compared those variations from nine additional breeds: beagle, Labrador retriever, German shepherd, Italian greyhound, English shepherd, Bedlington terrier, Portuguese water dog, Alaskan malamute, and rottweiler. They also compared these variations against those of four types of wolves and a coyote.
Scientists tracked short interspersed elements and found the boxer and the poodle differed at 10,562 locations. Expanding the study to other breeds showed at least 20,000 locations. These differences could act as signposts for genes linked to disease or traits, researchers said.
Two years ago, the Broad Institute began a two-part project to assemble a complete map of the dog genome. Researchers acquired a DNA sequence covering nearly 99 percent of the dog genome from a female boxer named Tasha and used the information to navigate the genomes of 10 other dog breeds and other related canines, such as the gray wolf and the coyote. Tasha's genome was used in both studies.
The Institute for Genomic Research compared Tasha's genome with Shadow, a standard poodle whose genome was published by The Institute for Genomic Research in 2003.
The Nature paper can be accessed here.
Researchers can access the sequence data through public databases such as the Dog Genome Resources, or at the Broad Institute web site.