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Chapter 4 – The science selected for study

4.7 Cedric and Clinky

The Devil researchers proposed that as devils on the east coast of Tasmania have succumbed to DFTD, it is possible that the DFTD-free devils on the west coast could be a resistant population. The research pathway dominated by the allograft theory, that the cancer was transmissible, meant that the competing hypothesis, that the cancer was caused by increasing use of pesticides in plantation forests on the eastern side of Tasmania, was ignored. The proposal that west coast devils could be resistant to the cancer was the basis for the vaccination trials on devils Cedric and Clinky. It was anticipated that resistance in a devil, or the development of a vaccine, could lead to a way to prevent for the Tasmanian devil cancer. Matthew Denholm published news of a

83 Dennis C, 2006, Time to Raise the Devil, Nature, Vol. 439, p 530

84 Breakthough in Tasmanian Devil Disease, Bio-Medicine, 2006, http://www.bio-medicine.org/medicine-news/Breakthrough-In-Tasmanian-Devil-Disease-7497-1/ 10 May 2009

85 There are a number of print, television, radio and electronic publications covering the story of Cedric and Clinky both national and international.

possible resistant devil in The Australian newspaper on 31 March 2008.86 The article stated that the devil Cedric had shown an immune response to DFTD, that he was the first devil to do so, and it was expected he would remain disease free. It was also suggested that devils with similar genes to Cedric could also be resistant to DFTD or capable of responding to a vaccine.

According to the immunogenic studies research notes (Appendix D) three devils from the western population were used in a trial to assess if devils could develop an immune response to a DFTD vaccination.87 The three devils were named Cedric and Klinky (aka Clinky) half-brothers and their mother Christine. Christine was a female devil from a Woolnorth population on the west coast of Tasmania. The research notes state Cedric was a male offspring from a wild mating, while Clinky was a male offspring from a captive mating with an Arthur River (west coast) male.88

Christine, according to the notes, developed no detectible immune response to a DFTD89 vaccination but developed tumours 16 weeks after being inoculated with DFTD cells. She was subsequently reimmunised against 4 different strains90 of DFTD and again developed tumours, which were removed. Following an examination in week 70 which showed no palpable tumours she was later found comatose and was euthanased. Cedric had developed no immune response to a DFTD vaccination at week

86 Denholm M, Hope of cure for dying Tasmanian devils, The Australian, 31 March 2008. Available at http://www.theaustralian.com.au/news/nation/hope-of-cure-for-dying-tasmanian-devils/story-e6frg6nf-1111115929033 last accessed 3 September 2010

87 These notes varied from the information provided to me in conversation with Alex Kreiss in Hobart on 14 November 2008. He was later to suggest that he had misunderstood my questions but my only question to him was – what is your role in the scientific research into the devil cancer?

88 These notes differ from the media reports where it is Cedric that is the offspring from a captive mating and who appeared to be resistant to the cancer.

89 Although it is termed Devil Facial Tumour (DFT) in the notes it is the same disease as Devil Facial Tumour Disease (DFTD) and I have maintained DFTD for consistency.

90 The inoculation of different strains of cancer would suggest that DFTD is in fact different cancers and is unstable previously referred to in Chapter 4.

41 and was subsequently challenged with strains 2 and 3 of the DFTD cancer. In week 90 Cedric also developed two facial tumours.91 Clinky, on the other hand developed a strong immunity to a DFTD vaccination when he was challenged at week 8. He was challenged again in week 30 with no obvious antibody response detected. In week 41 he was challenged this time with strain 2 and at week 53 developed tumours at inoculation sites.

The apparent resistance in one devil was claimed as a breakthrough.92 On the Save the Tasmanian Devil website in 2008, Associate Professor Greg Woods explained ‘this male devil (Cedric) was injected with dead DFTD tumour cells‘ and subsequently

‘Cedric produced an immune response as his body recognised the cancer cells as foreign’.93 Woods further explained ‘[d]evils don’t produce immune responses to DFTD because the diseased cells are too similar to their own cells’ he continues ‘[b]ut what we’ve found is that Cedric’s MHC is sufficiently different to the tumour or the diseased cells to be recognised as foreign’.94 It is further proposed that a west coast ‘group may be so genetically different that they are naturally resistant to the disease’.95 However, it was reported in the media on 17 December 2008 that Cedric had developed DFTD.96 It was not revealed until September 2010 that Cedric had been euthanised when X-rays revealed he had lung tumours.97

91 Sharman A, Welcome, Devil News, March 2009, DPIPWE, Hobart, p 2

92 Hayden EC, 2009, Genome scan may save Tasmanian devils from cancer, Nature News. Available at:

http://www.nature.com/news/2009/090303/full/news.2009.132.html last accessed 31 December 2012

93 Anon. 2008, Cedric’s life inheritance, Save the Tasmanian Devil. Available at:

http://www.tassiedevil.com.au/tasdevil.nsf/TheProgram/49364AFDF5B41207CA2576D2000DD302 last accessed 17 August 2010

94 ibid.

95 ibid.

96 Serious setback in race to save the Tasmanian devil, 17 December 2008. Available at http://origin-www.thewest.com.au/default.aspx?MenuID=28&ContentID=113744 last accessed 14 August 2010

97 The World Today with Eleanor Hall, ABC Radio National, Cedric the Tasmanian devil dies, 1 September 2010. Available at: http://www.abc.net.au/worldtoday/content/2010/s2999435.htm last accessed 3 September 2010

These experiments were to test whether or not the DFTD researchers could develop a vaccine, which would enable these devils to mount a resistance to DFTD. However, all three devils succumbed to the disease, which suggests the experiment failed. The results of the experiment have never been published and the cause of the devils’ cancers has not been explained. It is also not known if there were experimental controls on variables such as contaminants in the food and water or the environment of the devils in the experiment.

The discovery of resistance within the devil population or the development of a vaccine for DFTD does not appear likely within the foreseeable future. New researchers have now embarked on the sequencing of the entire devil genome to meet the challenges and enable a conservation project to maximize devil genetic diversity.