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DNA offers hope for Tasmanian icon

Road to destruction 1830 -- Van Diemens Land Co introduces thylacine bounties. 1888 -- Tasmanian Parliament places bounty on thylacine's head. 1909 -- Government bounty scheme terminated. 2184 bounties paid. 1926 -- London Zoo buys its last thylacine. 1933 -- Last thylacine captured, Florentine Valley, sold Hobart Zoo. 1936 -- World's last captive thylacine dies in Hobart Zoo. 1936 -- Tasmanian tiger added to the list of protected wildlife. 1986 -- Thylacine declared extinct by international standards. Source: Australian Department of Primary Industries, Water and Environment

From its vault in Sydney's Australian Museum, a pickled Tasmanian tiger pup has brought the prospect of reviving an extinct species to the verge of reality, bringing mixed reactions of wonder and terror.

More than 60 years after its extinction, the museum launched a project to clone the Tasmanian tiger, more correctly known as the thylacine, a lost icon of Australia's island state. This pup's DNA was the starting point, due to its remarkable state of preservation.

Three years later, geneticists believe the thylacine could conceivably be cloned within a decade.

For proponents, it is a chance to undo a terrible mistake that humans made. Human hunting was responsible for wiping out the thylacine in Tasmania, its final refuge. For diehard critics, it is "playing God."

The driving force behind the project is museum director Michael Archer, who dismisses the frequent comparisons with Jurassic Park, the Steven Spielberg film in which scientists recreate dinosaurs by cloning their DNA.

"The thylacine's world is not gone. The ecological system of which it was the top carnivore is still the same. I think we have a moral obligation to bring it back if we can do it," Archer told AFP. "I think this as a terrible thing humans did, and most religious people agree.

"I am not in any doubt that it will happen eventually. It is the geneticists who have been saying this could be done in 10 years."

The thylacine was hailed as a wonder of nature when Europeans first saw it. Although a marsupial which nurtured its young in a pouch, its appearance and behavior were strikingly similar to that of a dog.

It is considered a perfect case of "convergent evolution," where similar environments and lifestyles produce similar features in totally unrelated species.

But the introduction of the dingo had already eliminated it from mainland Australia. European farmers soon dubbed it a pest. None has been produced alive since 1936.

Archer says he suggested the animal might eventually be cloned 15 years ago, but generally got a dismissive response. Advances in genetic engineering and the arrival of Dolly the cloned sheep changed that. Then the museum's attention turned to the pup, which had been in its possession since 1866.

Remarkably little is known about it, not even where it was captured. Researchers have deduced that it had been in its mother's pouch for about four months and was nearly full term. It is assumed the mother must have been killed.

It was sent back from Tasmania by George Masters, then employed by the museum as a collector, who may have purchased it. By pure chance, whoever preserved it used alcohol, an unusual step which left most of its DNA intact more than a century later.

Work with its DNA provided the impetus to get the project going. However, genetic material has now been obtained from at least three individual thylacines, both male and female.

Thylacine remains from hundreds of animals are in collections around the world, so Archer says the possibility is wide open not just of cloning one animal but of eventually returning a viable population to the wild.

Archer even has images of Australians keeping thylacines as pets, as some people did in the 19th century.

Among the hurdles to be overcome is getting dead DNA to act again as living DNA. The DNA must be extracted and multiplied, using yeast or bacteria cells.

A suitable host animal will be needed, probably the thylacine's distant cousin, the Tasmanian devil. More needs to be known about that animal's breeding cycle and its DNA needs to be sequenced.

If the thylacine can be cloned, however, it has huge implications for conservation. Some critics fear people may cease to care about conservation at all.

Museum collections of bones and other once living artefacts will suddenly be more than mere historical curiosities. They will be time capsules which could be used to take species into the future.

Researchers say the project is massively underfunded. Only a single researcher has been working fulltime on the project, with limited laboratory facilities.

The roughly 120,000 Australian dollars (US$83,000) so far spent has been largely funded privately, partly by a trust with Tasmanian connections.

Archer and his colleagues are seeking more funding, promising in return one of the most exciting scientific projects of the present day.
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