Transmissible cancers are clonal cell lineages that can spread between individuals via transfer of living cancer cells. One of the oldest known contagious cancers is Canine Transmissible Venereal Tumour (CTVT). CTVT is usually sexually-transmitted between dogs and manifests as genital tumours. This dogged disease first arose from the cells of an early domesticated dog thousands of years ago and has since then "metastasized" through global dog populations. In their new study, Dr Elizabeth Murchison’s Group at the Department of Veterinary Medicine trace the historic origin of this cancer lineage using samples of DNA from ancient canids. The study reveals that CTVT first arose over eight thousand years ago in a “founder” individual very closely related to an extinct population of dogs that were once widespread across the Americas.
