A group of scientists hassequenced the genome of the Tasmanian devil ( Sarcophilus laniarius ), a carnivorous marsupial that can only be found on that Australian island and that isendangered by deadly facial cancerinfectious character calledDemons Facial Tumor(DFTD).
The DFTD, which disfigures the victim and causes death by starvation or drowning in a matter of months, emerged 15 years ago on the east coast of Tasmania and spread rapidly westward. It acts like a virus but spreads through a single cancer cell that appeared in a Tasmanian devil several decades ago. This malignant cell is spread by a bite, mating or mere contact. “Imagine a human cancer spread just by shaking hands. It would eradicate our species quickly,” suggests study lead author Stephan Schuster, a professor of biochemistry and molecular biology at Penn State University.
As published today by the magazinePNAS, the researchersanalyzed the complete genome of two Tasmanian devils, one of them resistant to two strains of evil -although it finally succumbed- and another sick, as well as the genome of a tumor taken from one of them. The animals were chosen for their genetic diversity as they came from the two furthest points on the island from each other. The data obtained will help determine the characteristics of the animals selected for captive breeding programs in Tasmania and mainland Australia, Schuster said.
According to Schuster, the genetic diversity of the Tasmanian devil is already low, one of the probable causes of its inability to create an immune response to these tumors. Hence, it is not enough for the genetically selected specimens to be resistant to DFTD, since we do not want to defeat only that evil but to develop healthy and genetically diverse individuals that can fight diseases and pathogens that have not yet evolved.
Schuster and his colleagues hope that their strategy against extinction canalso apply to other endangered species. 25% of land mammals are threatened.
