Zoobiquity by Barbara Natterson-Horowitz Page B

treatment was ultimately tested in more than 350 pet dogs—and prolonged life so well that more than half the animals who got the injections exceeded their cancer-shortened life expectancies.In 2009, Merial released the vaccine to veterinary oncologists, under the name Oncept, making the treatment available to thousands of family pets stricken with cancer.
    Wolchok’s four zoobiquitous words—“Do dogs get melanoma?”—sparked an intense collaboration, one that may have permanently changed the way veterinarians treat the disease in canine patients. And the translational potential is enormous. Bergman and Wolchok’s success is inspiring work on a similar vaccine for melanoma in humans. c
    Yet Bergman knows that, even with the success of Oncept, human medicine may still take a while to wake up to the possibilities of interspecies collaboration.
    “Almost without fail, when I tell this story to groups of human doctors,” he said to me—adding politely yet pointedly, “no offense to your colleagues”—“someone will come up to me afterward and ask, ‘How did you convince those dog owners to let you give their pets cancer?’ ” Bergman chuckled. “I have to explain. These are not lab dogs. We didn’t ‘give’ them cancer.”
    What he actually gave them was another shot at life.
    * Sadly, Linda Munson, the U.C. Davis veterinary pathologist leading the research, died before the jaguar genome was fully sequenced and scanned for clues to BRCA1 relevance, although her early research pointed to a connection.
    † Here I should pause to dispel the myth—often repeated—that sharks “don’t get cancer.” Tumors of many kinds, some metastatic, have been found in numerous species of sharks. Rumors to the contrary are likely promulgated by those hawking alternative remedies at the expense of wild species.
    ‡ According to the WHO, “a region that extends from West to East Africa between the 10th degree north and 10th degree south of the equator and continues south down the Eastern coast of Africa.”
    § Cats have served as sentinels, too: one study linked oral cancer in cats to environmental tobacco smoke.
    ‖ When certain populations show the same mutation, it’s usually a result of the “founder effect.” That’s when a long line of descendants arises from a very few progenitors and for some reason—geographic, cultural—remains isolated. The founder effect has been noticed in populations from microbes and plants to animals, including humans. The mutation that causes cystic fibrosis, for example, can be traced to one person. The founding individual who first carried the BRCA1 mutation in Ashkenazi Jewish families is thought to have lived more than two thousand years ago.
    Geneticists frequently see founder effects in bottleneck populations. These are groups where certain factors mean that many descendants come from few ancestors. Cheetahs are a natural bottleneck population. As their numbers dwindle, they rely on the genes of fewer and fewer breeding members to keep their species alive. This is an issue for many endangered species. With domesticated dogs, we humans create bottleneck populations on purpose: by breeding all future descendants from a set number of progenitors, we limit the genes in that pool, including the mutated ones.
    a It’s calledxenogeneic plasmid DNA vaccination. Essentially, it “hides” proteins from a foreign species within the cells of a patient with cancer. When these foreign proteins circulate through the blood and lymph, the immune system senses the alien proteins. It thinks there’s an invader afoot, and mounts an attack on its own cells. Getting the immune system to attack itself is called “breaking tolerance”—and it’s so hard, said Bergman, that it’s the “holy grail of cancer immunotherapy.”
    b From a
human
melanoma cell donated by an anonymous patient, the gene jocks at Sloan-Kettering extracted human tyrosinase cDNA. They shaped each strand into a