Scientists Report Findings on Origin of a Cancer in Tasmanian Devils - NYTimes.com

Scientists Report Findings on Origin of a Cancer in Tasmanian Devils - NYTimes.com: "A team of Australian and American scientists has now followed up on Dr. Belov’s study, using more powerful gene-sequencing technology to take a closer look at a larger number of Tasmanian devils. To trace the origin of the tumors, the scientists looked at individual cancer cells, recording which genes were active. They found a set of genes normally active only in a type of nerve cell known as Schwann cells. They argue that a single Schwann cell in a single animal was the progenitor of all the devil facial tumor disease cells.

“The lack of genetic variation suggests that the tumors are young,” said a co-author of the study, Tony Pappenfuss, a bioinformatician at the Walter and Eliza Hall Institute of Medical Research in Australia.

Scientists have found only one other case in which cancer cells naturally spread like parasites, a disease in dogs known as canine transmissible venereal tumor. Comparisons of tumors collected from dogs around the world indicate that they descend from a single ancestral cell that existed several thousand years ago. Ever since, the tumor cells have evolved to move among hosts and avoid their immune systems."