Genetic Cancer Link Between Humans And Dogs Discovered

Cancer researchers at the University of Minnesota and North Carolina State University have found that humans and dogs share more than friendship and companionship -- they also share the same genetic basis for certain types of cancer. Furthermore, the researchers say that because of the way the genomes have evolved, getting cancer may be inevitable for some humans and dogs. Their findings are published in the journal Chromosome Research, in a special edition on comparative cytogenetics and genomics research. Genomes are divided into chromosomes, which act as nature's biological filing cabinets with genes located in specific places.
"Many forms of human cancer are associated with specific alterations to the number or structure of chromosomes and the genes they contain," Breen said. "We have developed reagents to show that the same applies to dog cancers, and that the specific genome reorganization which occurs in comparable human and canine cancers shares a common basis."
More specifically, Breen and Modiano found that the genetic changes that occur in dogs diagnosed with certain cancers of the blood and bone marrow, including chronic myelogenous leukemia (CML), Burkitt's lymphoma (BL), and chronic lymphocytic leukemia (CLL), are virtually identical to genetic abnormalities in humans diagnosed with the same cancers. According to Breen and Modiano, dogs are good research subjects because they develop the disease spontaneously, and many of the modern breeds have developed over the past few hundred years using restricted gene pools. This selective breeding has preserved the genetics of a breed. It has also made some breeds more susceptible to certain cancers. These factors, coupled with the high degree of similarity between the genomes of dogs and humans, provided the researchers with an opportunity to compare the genomes and study the evolutionary genetic changes associated with cancer.