- Contagious cancer has already decimated populations of Tasmanian Devils in Australia.
- In 2014, scientists discovered a second form of transmissible cancer in Tasmanian Devils.
- Discovery of the new cancer opens up the possibility that transmissible cancers may not be as rare in nature as we previously thought, scientists say.
In 1996, researchers discovered a deadly cancer in Australia’s Tasmanian Devils. The transmissible cancer jumps from one Tasmanian Devil to another, and is often fatal to the animals. Since its discovery, the contagious cancer has wiped out over 90 percent of Tasmanian Devils in some areas.
Now, researchers have discovered a second contagious cancer in these endangered marsupials, according to a study published last week in the journal Proceedings of the National Academy of Science. This second cancer, first detected in a devil in south-east Tasmania in 2014, is genetically distinct from the first one, researchers from the University of Tasmania, Australia, and the University of Cambridge, UK, have found.
“The second cancer causes tumors on the face that are outwardly indistinguishable from the previously-discovered cancer,” lead-author Ruth Pye from the Menzies Institute for Medical Research at the University of Tasmania, said in a statement. “So far it has been detected in eight devils in the south-east of Tasmania.”
Normally, cancers are not contagious. Only four forms of transmissible cancers have been found in nature so far, in Tasmanian Devils, dogs, Syrian hamsters and soft-shell clams. In the Tasmanian devils, the cancer spreads when the devils bite each other’s faces during fights for food, and at the time of mating. But the recent discovery of a second contagious cancer in the devils shows that transmissible cancers may not be as rare in nature as researchers previously thought, Elizabeth Murchison from the Department of Veterinary Medicine at the University of Cambridge, said in the statement.
“Previously, we thought that Tasmanian devils were extremely unlucky to have fallen victim to a single runaway cancer that emerged from one individual devil and spread through the devil population by biting,” she said. “However, now that we have discovered that this has happened a second time, it makes us wonder if Tasmanian devils might be particularly vulnerable to developing this type of disease, or that transmissible cancers may not be as rare in nature as we previously thought.”
The discovery also opens up the possibility that there may be other transmissible cancers in Tasmanian devils that researchers haven’t detected yet, researchers say.
- Pye, RJ et al. 2015. A second transmissible cancer in Tasmanian devils. PNAS; doi: 10.1073/pnas.1519691113