BOB HIRSHON (host):
A contagious canine cancer. I’m Bob Hirshon and this is Science Update.
Scientists have confirmed that a cancer tumor in dogs acts like a parasite, passing from dog to dog during sexual contact. Virologist Robin Weiss of University College London led a team that collected samples of these tumors from dogs around the world. He says they found that the tumors were genetically the same as each other but genetically different from their hosts.
ROBIN WEISS (University College London):
What does this mean? It means that a cancer cell has come out of one dog—or we think it may have been a gray wolf—hundreds of years ago and has spread across the world of dogs. It’s a cancer cell that has become contagious.
Scientists have documented only one other case of a contagious tumor, but scientists say this sort of cancer is exceptionally rare and nothing like it afflicts humans.
I’m Bob Hirshon, for AAAS, the science society.