

In a process that sounds like Jurassic Park but is closer to the cloned sheep Dolly, Australian scientists are bringing an extinct amphibian back to life.

The gastric-brooding frog, which swallowed its eggs, grew its young in its stomach and gave birth through its mouth, became extinct about 30 years ago.

But scientists working on the “Lazarus project” have successfully reactivated its DNA and produced an embryo.

Prof Mike Archer of Sydney’s University of New South Wales said the gastric-brooding frog was an extraordinary creature.

“In the stomach these eggs went on to develop into tadpoles and the tadpoles then went on to develop into little frogs,” he told ABC radio.

“And like any pregnant mum, when you have little babies rattling away in your stomach saying, ‘let me out’, she would then open her mouth and out would pop little frogs.

“The first people that saw that were aghast. By the time anybody got excited about it, suddenly it was extinct.”

The team, which also includes researchers from the University of Newcastle north of Sydney, found some gastric-brooding frog carcasses stored in a deep freezer and were able to recover tissue.

Using a technique called somatic cell nuclear transfer, they implanted the dead cell nucleus from the extinct species into an egg from another frog species. From this, the scientists created an embryo.

“There was one day in the laboratory that was so exciting when all of a sudden the egg from this living species that had had one of these extinct frogs’ nuclei inserted into it started to divide, and then divide again,” Prof Archer said. “We were holding our breath and then it just kept going . . . It went on to develop an embryo.”

Though the embryo has so far only survived 36 hours, the Lazarus project team is confident that producing a tadpole is the next step.

“We are in a research zone beyond where anyone else has been before and there’s no signpost,” Prof Archer said.