Frozen Mice Cloned – Are Woolly Mammoths Next?
Japanese scientists have cloned mice whose bodies were frozen for as long 16 years and said on Monday it may be possible to use the technique to resurrect mammoths and other extinct species. Mouse cloning expert Teruhiko Wakayama and colleagues at the Center for Developmental Biology, at Japan’s RIKEN research institute in Yokohama, managed to clone the mice even though their cells had burst.
“Thus, nuclear transfer techniques could be used to ‘resurrect’ animals or maintain valuable genomic stocks from tissues frozen for prolonged periods without any cryopreservation,” they wrote in the Proceedings of the National Academy of Sciences. Wakayama’s team used the classic nuclear transfer technique to make their mouse clones. This involves taking the nucleus out of an egg cell and replacing it with the nucleus of an ordinary cell from the animal to be cloned.
When done with the right chemical or electric trigger, this starts the egg dividing as if it had been fertilized by a sperm. “Cloning animals by nuclear transfer provides an opportunity to preserve endangered mammalian species,” they wrote.
“However, it has been suggested that the ‘resurrection’ of frozen extinct species (such as the woolly mammoth) is impracticable, as no live cells are available, and the genomic material that remains is inevitably degraded,” they said.
