Scientists Mark 'Significant Step' in Bringing Back Woolly Mammoths

It has been working for about 20 years on a project to use cloning to resurrect mammoths, an animal that has always been extinct.

But boffins in Japan reckon they could roam the Earth once again after making a massive breakthrough. The latter is supposed to undergo genetic division to ultimately set the mammoth revival project in motion, with an egg cell forming in the mouse's ovaries.

The project by an worldwide team took cell nuclei from a well-preserved mammoth discovered in 2011 in Siberian permafrost and placed them into several dozen mouse egg cells.

Despite certain complications due to "due to the extensive DNA damage in the transferred nuclei", the research and transplantation itself marked a remarkable "step toward bringing mammoths back from the dead", Kei Miyamoto, one of the study's authors, told Japan's Nikkei media outlet.

When inserted into mouse ova, five out of 43 nuclei were observed to develop to a point just before the nuclei would split in two as a result of cell division. Their observations also suggested the injection of mammoth nuclei triggered DNA fix machinery in mouse oocytes.

As a first step, the team, from Kindai University in Osaka, confirmed the authenticity of Yuka's extracted tissue samples using whole-genome sequencing techniques.

Miyamoto and his colleagues are working with researchers in Russian Federation to bring mammoths back to life using cloning technology called somatic cell nuclear transfer.

Following the procedure, the scientists reported a "pronucleus-like structure budded from the injected ... mammoth nucleus".

"We need new technology, we want to try various approaches", Miyamoto said. "We still have a long way to go".