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AN UPDATE ON DEVIL FACIAL TUMOUR DISEASE IN TASMANIAN DEVILS Alexandre Kreiss Menzies Research Institute Tasmania The Tasmanian devil (Sarcophilus harrisii), the world’s largest marsupial carnivore endemic to Tasmania, is facing extinction due to an emergent transmissible cancer, devil facial tumour disease (DFTD). This disease is clearly an important problem and devils have been recently upgraded to ‘endangered’ under the Tasmanian and Commonwealth of Australia listings. The disease was first recognised in the far north east of Tasmania, in 1996. Since then, it has spread south and west and now affects devils in over 60% of the island. The disease affects predominantly animals of breeding age and older, therefore, a complete crash in the adult population is observed soon after DFTD arrival (Hawkins et al. 2006). Juvenile breeding (and therefore DFTD infection) has been observed in areas where adult devils are absent due to the tumour (Jones et al. 2008). DFTD is one of only two transmissible cancers in existence, the other being the canine transmissible venereal tumour. DFTD is transmitted during biting and these tumours are not rejected by the host immune system, despite being a ‘cell allograft’ (Pearse and Swift 2006; Siddle et al. 2007; Murchison et al. 2010). DFTD tumour cells are of Schwann cell origin and are found predominantly on the face and mouth tissues. Metastasis to distant organs, such as lung, kidney and local lymph nodes are common. Affected devils die of starvation, secondary infection in the tumour or due to metastasis to vital organs, usually six to 12 months after the tumour is first visible (Hawkins et al. 2006; Loh et al. 2006). Many aspects of the disease are still unknown (such as the mechanism of tumour acceptance and the incubation period), but it is likely that most transmission occurs during the breeding season, when animals have a greater contact with each other. No resistance has been found in the wild and the only current management strategy to protect the species is the establishment of insurance populations. Without a cure or prevention, the species faces extinction in 20-30 years (McCallum et al. 2007). Suggested reading: Pearse AM, Swift K (2006) Allograft theory: transmission of devil facial-tumour disease. Nature 439: 549. Hawkins CE, Baars C, Hesterman H, Hocking GJ, Jones ME, et al. (2006) Emerging disease and population decline of an island endemic, the Tasmanian devil Sarcophilus harrisii. Biological Conservation 131: 307-324. Murchison EP, Tovar C, Hsu A, Bender HS, Kheradpour P, et al. (2010) The Tasmanian devil transcriptome reveals Schwann cell origins of a clonally transmissible cancer. Science 327: 84-87. Loh R, Bergfeld J, Hayes D, O'Hara A, Pyecroft S, et al. (2006) The pathology of devil facial tumor disease (DFTD) in Tasmanian devils (Sarcophilus harrisii). Vet Path 43: 890-895. Tovar C, Obendorf D, Murchison EP, Papenfuss AT, Kreiss A, et al. (2011) Tumor-Specific Diagnostic Marker for Transmissible Facial Tumors of Tasmanian Devils: Immunohistochemistry Studies. Vet Pathol 48(6): 1195-203. Kreiss A, Cheng Y, Kimble F, Wells B, Donovan S, et al. (2011). Allorecognition in the Tasmanian Devil (Sarcophilus harrisii), an Endangered Marsupial Species with Limited Genetic Diversity. PLoS One 6(7): e22402.