Japanese clone mouse from frozen cell, aim for mammoths
Scientists at the government-backed research institute Riken used the dead cell of a mouse that had been preserved at minus 20 degrees Celsius (minus 4 degrees Fahrenheit) -- a temperature similar to frozen ground.
The findings were published in the Proceedings of the National Academy of Sciences in the United States.
"The newly developed technology of nucleus transfer greatly improved the possibility of reviving extinct animals," the research team led by Teruhiko Wakayama said in a statement.
But the researchers said tough challenges remain ahead on how to restore extinct animals, which would require breeding with animals that are still alive.