Interesting medical news from the New York Times.
Dogs May Help Find Genes That Cause Cancer
By ANDREW POLLACK
About half of all Bernese mountain dogs are prone to an unusual blood cancer called malignant histiocytosis. Boxers are four times more likely to get lymphomas than dogs in general, while Pomeranians are 10 times less likely. Cocker spaniels are more likely to get B cell lymphomas, and huskies are more susceptible to T cell lymphomas.
Such differences among breeds provide evidence that the risk of getting cancer is at least partly inherited. And they suggest that dogs could be useful in the search for genes that cause cancer, with the findings probably applicable to people, as well.
The role of heritability is easier to track in dogs than in people,” said Jaime F. Modiano, a veterinarian and immunologist at the University of Colorado, who said it had been difficult to find many cancer-risk genes in people.
Dogs are ideal for such studies because there is relative genetic homogeneity in a breed. And it is possible to have five or six generations of dogs alive at the same time, providing ample genealogical information.
Dr. Modiano is one of about 15 academic and government scientists who are forming the Canine Comparative Oncology and Genomics Consortium, a nonprofit group, to look for cancer genes in dogs. The group is separate from the National Cancer Institutes recently formed team of veterinary hospitals to test cancer drugs in dogs, although the two groups have members in common.
One goal of the new genetics organization is to assemble a collection of tumor samples and DNA from dogs to be used in studies.
Other necessary tools are also becoming available. The complete genome sequence of a dog a boxer was published last year.
Scientists led by Elaine A. Ostrander, now at the National Human Genome Research Institute, have already discovered a genetic mutation responsible for a rare syndrome that causes kidney cancer and skin nodules in German shepherds. The mutation was in a gene also involved in a similar rare human disease called Birt-Hogg-Dube syndrome.
Hunts are going on now for other cancer-risk genes like the one for the cancer in Bernese mountain dogs and for bone cancer in Rottweilers.
Dogs have and are being used to find genes related to other diseases as well. A discovery in the late 1990s of a mutation responsible for inherited narcolepsy in Doberman pinschers provided clues to understanding how sleep is regulated.
Whats new here is trying it for cancer,” Dr. Modiano said, because cancer has been a particularly elusive disease to try to find heritable traits.”
