Dog (image) Arizona State University Share Print E-Mail Caption CTVT first emerged in a dog that lived 4-8.5 thousand years ago. All CTVT tumours carry the DNA belonging to this 'founder dog'. By counting and analysing the mutations acquired by CTVT tumors around the world, researchers can piece together how and when CTVT emerged and spread. Artist's impression of the 'founder dog' that first gave rise to CTVT. This dog's phenotypic traits were interpreted from the genetic variation found in the DNA of the cancer that it spawned. Credit Emma Werner Usage Restrictions None Share Print E-Mail Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.