Environment

Tasmanian devil facial cancer origins 'identified'

by stejeb | January 1, 2010 at 08:18 am

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Environmentalists have seen numbers of the largest carnivorous marsupial, the Tasmanian Devil, shrink by 60% over the last decade due to a transmissible cancer.

They used to exist on the Australian mainland but became extinct there 600 years ago because of dingoes, they are found now only in Tasmania, living across the whole island apart from a small area in the south west. Living where there is dense bush or scrub-land they make their homes in hollow logs or rocks.

They're not good hunters so they prefer to scavenge, although They will kill birds and small animals. They'll eat everything, bones, fur and everything else. They eat possums, small wallabies, kangaroos, reptiles, they steal eggs, basically they'll eat anything, which is good for the farmers because they clear up dead animals and stop disease from spreading.

Living up to 8 years, they start to breed at 2, giving birth to up 20 babies at a time, which are about the size of the top of a matchstick. Only 4 will make it to the pouch however, as that is all that can live in the pouch.

Scientists are hoping that with the new findings they will eventually be able to make a vaccine to prevent the facial cancer, or find a treatment for it.

Researchers believe they have identified the source of fatal tumours that threaten to wipe out the wild population of Tasmanian devils.

Writing in Science, an international team of scientists suggest cells that protect nerves are the likely origin of devil facial tumour disease (DFTD).

The disease is a transmissible cancer that is spread by physical contact, and quickly kills the animals.

DFTD has caused the devil population to collapse by 60% in the past decade.

"To look more closely at the tumours' origin, we sequenced the genes that are expressed in this devil cancer and compared them with other genes that are expressed in other devil tissues," explained lead author Elizabeth Murchison, from the Australian National University in Canberra.

She told the Science podcast the team's findings delivered surprising results.

"We found that the tumours expressed genes that were normally only expressed by Schwann cells, which are cells that are found in the peripheral nervous system that protect nerves."