Scientists used cloning technology to create an embryo of one of the strangest frogs ever to live.
The extinct gastric-brooding frog, Rheobatrachus silus, was remarkable in that it gave birth to its young through its mouth, incubating its eggs in its stomach.
The frog has been extinct since the last living member of the species died in 1983, but tissues from the frog were collected in the 1970s and stored in a conventional deep freezer. Researchers from the Lazarus Project, named for the biblical character brought back to life by Jesus, have successfully created an embryo of the mouth-birthing frog from the 40-year-old frozen tissue.
Using a method called somatic cell nuclear transfer, scientists from the Lazarus Project removed “dead” cell nuclei from the frozen tissue and implanted them into healthy, “fresh” egg cells from a distant relation of Rheobatrachus silus, the Great Barred Frog. Some of these new hybrid eggs began to spontaneously divide, growing into embryos.
“We've reactivated dead cells into living ones and revived the extinct frog’s genome in the process. Now we have fresh cryo-preserved cells of the extinct frog to use in future cloning experiments,” Mike Archer, leader of the Lazarus Project and a professor at the University of New South Wales, told the Daily Mail. “We’re increasingly confident that the hurdles ahead are technological and not biological and that we will succeed.”
Unfortunately, none of the embryos lived past a few days, but tests reveal that they did contain the genetic material of the extinct frog. While the study was unsuccessful in creating a living frog, the research shows that bringing back extinct species using cloning technology and preserved tissues may be possible. Unfortunately, if it is possible, the first animals brought back from extinction probably won’t be the dinosaurs of Jurassic Park.
At last week’s TEDx DeExtinction event, international researchers met to discuss bringing back extinct species, with among the possible candidates the woolly mammoth, New Zealand’s flightless giant moa bird, the dodo and the Cuban red macaw.