Unscrambling the Devil Tumor

Courtesy of variationblogr

Researchers have mapped the genome of the Tasmanian Devil for the first time, a crucial step toward understanding the transmissible facial tumors decimating Devil populations and related human cancers.

The international team, led by Dr. Janine Deakin of the Research School of Biology at The Australian National University, compared the normal Tasmanian devil genome to that of the devils with facial tumors and found that significant fragments of the chromosomes had been jumbled, like a jigsaw puzzle put together the wrong way. Their research is published in this month’s edition of PLoS Genetics.

The first case of devil facial tumor disease was recorded in 1996. While Devils can die from the cancer, thousands more have died through starvation, as the disease deforms their faces so badly that they can’t eat. The aggressive carnivores contract the cancer through biting and jaw wrestling with Devils that are already infected.

Deakin’s team found that, surprisingly, the devil tumor is evolving very slowly and has changed very little since its emergence 16 years ago.

“That’s really unusual for cancers, because usually — for human cancers — evolution is rapid and the tumor will be completely different between the original tumor and its metastases. In this work, we confirmed that the devil tumor is genetically very stable,” Deakin said.

Researchers hope that, by unlocking the secrets of this slowly evolving cancer, they will understand not only the devil tumor, but also the way human cancers develop.

“In humans, you are usually working with a rapidly evolving cancer, and it’s hard to identify the important things because it’s all happening so fast. The devil is going to be a good model for looking at some human cancers, because it is so stable — with everything happening slower, we have a better chance of finding those things out,” she said.

The Tasmanian Devil has recently been listed as an endangered animal, and it’s predicted to become extinct in 25 to 35 years unless a cure can be found.