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The Tasmanian devil is the world's largest carnivorous marsupial, it's about the size of a small dog
And it lives only in the island of Tasmania, which is that small island just to the south of the mainland of Australia
And now the Tasmanian devil is now undergoing a really rapid population decline and that's because of the emergence of a new disease, which is an infectious cancer
The cancer was first observed in 1996 in the north east of Tasmania and quickly it spread to other parts of Tasmania
and now the population has declined by between 60 and 70 per cent
Tasmanian devil cancer is a highly unusual tumour because this particular cancer is spread from animal to animal
The actual cells are inoculated from the tumour of one Tasmanian devil into the next one because they engage in biting each other
Through feeding practices and through mating
We've been very interested in the genetics of the Tasmanian devil transmissible cancer because it's actually one cancer
that arose once, in one devil and has now spread through the population, almost like it has metastasised through the entire population
Our genomic work has allowed us to do some genetic detective work to understand the identity of that original devil
That first gave rise to the cancer and our work suggests that that devil was a female, that she probably lived on the east coast of Tasmania
relatively recently. I call her the 'Immortal devil' because although she is now dead, the descendants of her cells and her DNA
are still present in the cancers of 1000s of devils around Tasmania today
So the evidence we have at the moment is that the immune system of the Tasmanian devil, the animal itself
is intact and functioning properly. So there must be something within the cancer that allows it to evade the immune system
And we now should use the genome sequences that we've generated in order to find what it is that the cancer is using to escape immune surveyance.
In one particular population we observed what looks like a selective sweep, which means that one cancer strain got over taken
by another one within the space of a few years which suggests that the cancer is continuing to evolve
It is not impossible that such a phenomenon could occur in human beings. We know that individual cancers have transferred between one human being and another
Thankfully they have not spread beyond that. But by learning about what is unique about the Tasmanian devil cancer
That allows it to spread through the whole species, we will be armed should such an event ever happen in human beings
What we plan to do next is to sequence more Tasmanian devil cancers and to look at how the cancers have spread and changed
genomically over time and space. This is going to give us some detail into how transmissible cancers evolve and also more broadly
how cancers themselves can evolve and change and adapt to their hosts over time
The future is looking quite bleak for the Tasmanian devil. The population is declining extremely fast
and the disease is spreading into all the areas that are still unaffected
Am, and so it's a race against time to find information and strategies and management interventions that can help save the devil from extinction
Before it's too late