Feeds

Tasmanian tumours blamed on inbreeding

Devils face visit from the Darwinator

Intelligent flash storage arrays

Warning: Graphic content More evidence, if it were needed, that no good can come of indulging in cousin-coitus. The Tasmanian devil, the grouchy doglike marsupial immortalised in the form of Warner Bros character Taz, is facing extinction due to a rampant communicable cancer.

Tasmanian devil tumour

The gruesome effects of DFTD.

Researchers have concluded that the rapid spread of the cancer, which has halved the devil population in just over a decade and may obliterate it altogether in another, is due to a lack of genetic diversity.

The flourishing Devil Facial Tumour Disease (DFTD) seems to pass easily from one animal to another during fights over food and mates. The devils are generally free with their teeth in such skirmishes, but the smallest of wounds to the mouth can result in death within six months as the cancer takes hold. Tumours sprout around the head and face, sometimes displacing eyes and teeth, and make it impossible for the animals to feed, inevitably leading to death from starvation.

The disease is one of only two known naturally-occurring infectious cancers - dogs and other canines can contract Canine Transmissable Venereal Tumour (CTVT) through copulation, but it is by no means always fatal.

Scientists have been struggling to find out the secret of DFTD's success in killing devils, whose population has fallen to around 75,000 from 150,000 in 1996. A collaborative project between the Sydney and Tasmania Universities, published this week online in the journal Proceedings of the National Academy of Sciences (pdf here), has made the breakthrough discovery that the devils' immune system - unlike that of dogs suffering from CTVT - simply does not fight the cancer because of a lack of genetic variation within the population.

The most important immune system gene region, the Major Histocompatibility Complex (MHC), has lost its healthy diversity in Tasmanian devils over time - the MHC of the tumour corresponds too well to that of the infected animals for their system to be inclined to combat it.

This means that otherwise robustly healthy animals can succumb quickly to DFTD, since their bodies do not recognise it as a threat. Rather, the cells are embraced by the animal's system as their own - the cells in all infected devils are genetically identical, making contraction of the cancer more like a sort of malign transplant.

A "Noah's Ark" project should ensure the survival of the species, with disease-free "insurance populations" being bred in safe areas. In theory, when DFTD is extinct the healthy colonies can be reintroduced - however, the ecological impact of the devils' rapid disappearance from the wild may be dire.

Providing a secure and efficient Helpdesk

More from The Register

next story
GRAV WAVE DRAMA: 'Big Bang echo' may have been grit on the scanner – boffins
Exit Planet Dust on faster-than-light expansion of universe
SpaceX Dragon cargo truck flies 3D printer to ISS: Clawdown in 3, 2...
Craft berths at space station with supplies, experiments, toys
That glass of water you just drank? It was OLDER than the SUN
One MEELLION years older. Some of it anyway
NASA rover Curiosity drills HOLE in MARS 'GOLF COURSE'
Joins 'traffic light' and perfect stony sphere on the Red Planet
Big dinosaur wowed females with its ENORMOUS HOOTER
That's right, Doris, I've got biggest snout in the prehistoric world
Japanese volcano eruption reportedly leaves 31 people presumed dead
Hopes fade of finding survivors on Mount Ontake
Relive the death of Earth over and over again in Extinction Game
Apocalypse now, and tomorrow, and the next day, and the day after that ...
prev story

Whitepapers

A strategic approach to identity relationship management
ForgeRock commissioned Forrester to evaluate companies’ IAM practices and requirements when it comes to customer-facing scenarios versus employee-facing ones.
Storage capacity and performance optimization at Mizuno USA
Mizuno USA turn to Tegile storage technology to solve both their SAN and backup issues.
High Performance for All
While HPC is not new, it has traditionally been seen as a specialist area – is it now geared up to meet more mainstream requirements?
Beginner's guide to SSL certificates
De-mystify the technology involved and give you the information you need to make the best decision when considering your online security options.
Security for virtualized datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.