"Extinct Tasmanian tiger gene brought back to life"

Scientists said Tuesday they had "resurrected" a gene from the extinct Tasmanian tiger by implanting it in a mouse, raising the future possibility of bringing animals such as dinosaurs back to life.

In what they describe as a world first, researchers from Australian and US universities extracted a gene from a preserved specimen of the doglike marsupial -- formally known as a thylacine -- and revived it in a mouse embryo.

"This is the first time that DNA from an extinct species has been used to induce a functional response in another living organism," said research leader Andrew Pask of the University of Melbourne.

The announcement was hailed here as raising the possibility of recreating extinct animals.

Mike Archer, dean of science at the University of New South Wales who led an attempt to clone the thylacine when he was director of the Australian Museum, called it "one very significant step in that direction."

"I'm personally convinced this is going to happen," he told the Australian Broadcasting Corporation. "I've got another group working on another extinct Australian animal and we think this is highly probable."

[. . .]

But Renfree also cautioned that the recreation of extinct animals was not the aim of the research.

"Maybe one day this might be possible but it won't happen in my lifetime," she told AFP. "It might happen in my children's lifetime, but there's so many steps we need to achieve before you could actually make this work."

PLoS ONE 3(5): e2240. doi:10.1371/journal.pone.0002240

Resurrection of DNA Function In Vivo from an Extinct Genome

Andrew J. Pask et al.


There is a burgeoning repository of information available from ancient DNA that can be used to understand how genomes have evolved and to determine the genetic features that defined a particular species. To assess the functional consequences of changes to a genome, a variety of methods are needed to examine extinct DNA function. We isolated a transcriptional enhancer element from the genome of an extinct marsupial, the Tasmanian tiger (Thylacinus cynocephalus or thylacine), obtained from 100 year-old ethanol-fixed tissues from museum collections. We then examined the function of the enhancer in vivo. Using a transgenic approach, it was possible to resurrect DNA function in transgenic mice. The results demonstrate that the thylacine Col2A1 enhancer directed chondrocyte-specific expression in this extinct mammalian species in the same way as its orthologue does in mice. While other studies have examined extinct coding DNA function in vitro, this is the first example of the restoration of extinct non-coding DNA and examination of its function in vivo. Our method using transgenesis can be used to explore the function of regulatory and protein-coding sequences obtained from any extinct species in an in vivo model system, providing important insights into gene evolution and diversity.

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