Contagious Cancer Found in Dogs

Scientists in England have gathered definitive evidence that a kind of cancer in dogs, known as Sticker’s sarcoma, is contagious. It is spread by tumour cells getting passed from dog to dog through sex or from animals biting or licking each other. Robin Weiss and his colleagues did genetic studies on the tumour cells from 40 dogs with Sticker’s sarcoma, collected from five continents, which showed that all the tumour cells are clones of each other. The parent cell probably arose in a domesticated dog of Asian origin — perhaps a husky — hundreds of years ago, and perhaps more than 1,000 years ago. A similarly transmissible cancer has recently been discovered spreading through populations of Tasmanian devils