Our Research Focus

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I’m Janine Deakin, an Associated Professor in
genetics

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and an ARC future fellow within

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the Institute of Applied Ecology at the
University of Canberra

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My research area is in comparative genomics.

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This literally means comparing the
genomes of one species

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to another to gain an understanding of how 
the genome has changed

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over the time. I'm particularly interested

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in the genomes of the unique fauna 
of Australia, such as marsupials like the Tammar 

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wallaby

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and Tasmanian devil and monotremes
like the platypus.

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I've recently started work on an Australian
reptile

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the central bearded dragon. My current
research topic is on

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the iconic Tasmanian devil and the
devastating devil facial tumour disease

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that is currently threatening

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the survival of the devil population.
This disease

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is unusual in that it is a contagious
cancer. It is not spread by a virus

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but it appears that the tumour itself is the
infectious agent,

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being spread by healthy Devils biting
into the tumours of

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infected Devils. Biting each

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other around the face is a social
behavior they displayed during mating

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and communal feeding. The tunour originated in

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an animal over 17 years ago and
has outlived its original host

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and has since passed through thousands of devils. 
My research

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on this disease has involved
comparing the normal devil genome 

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to that of the tumour to see how the  
tumour was initially formed

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and how it is evolving as it 
spreads throughout the population.

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By determining the location of genes 

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a normal devil and tumour chromosomes, we 
found that the devil facial tumour initially

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developed

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in a female devil. We came to this conclusion 

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because there was no why Y chromosome 
genetic material found in the tumour

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and most of the X chromosome genes 
were found in two copies,

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as we would expect for females. Our data 
also provided some insight into how the tumour

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was initially formed.

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It appears that two chromosomes 
were shattered

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and re-joined in a completely different order. 
What would have caused this event

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is unknown but knowing which regions 
of the genome are highly rearranged 

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gives us a starting point for looking 
for candidate genes involved in 

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driving this tumour. 

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We have also observed that since 
this initial shattering

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and re-joining event, the tumour 
has become relatively stable. 

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This is quite remarkable given that 
the tumour has been dividing

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for over 17 years. By continuing to 
observe how the tumour is evolving, 

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we will be able to determine if the 
tumour is changing to overcome 

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any possible resistance it meets within 
the devil population,

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which is a situation we hope 
is not happening. 

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Alternatively, the tumour may be 
evolving to become less virulent 

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to devils, allowing devils to 
ultimately survive 

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and overcome a tumour infection.