KINOKAWA, Wakayama Prefecture--Scientists confirmed signs of activity in the nuclei of cells extracted from the 28,000-year-old remains of a woolly mammoth, fostering hopes of resurrecting the extinct ancient species.

The international research team led by Akira Iritani, a professor emeritus at Kindai University here, published the research results on March 11 in the British magazine Scientific Reports.

The team collected muscle and bone-marrow tissues from the legs of “Yuka,” a female mammoth retrieved from the Siberian permafrost in northern Russia in 2010.

Yuka, 3.5 meters in length, has been kept in good condition.

The researchers extracted the nucleus of each cell that carries biological hereditary information, and those nuclei were injected into mouse oocytes.

The confirmed activity, similar to the one that occurs right before a cell divides, was likely possible because of the ability of mouse oocytes to restore DNA, they said.

However, reviving the mammoth would require cells to divide and multiply, and the team did not achieve this process.

“We were able to observe the activities of cell nuclei extracted from the remains of an ancient order from at least 28,000 years ago,” said Kei Miyamoto, a lecturer in the Department of Genetic Engineering at Kindai University’s Faculty of Biology-Oriented Science and Technology. “Once we obtain cell nuclei that are kept in better condition, we can expect to advance the research to the stage of cell division.”

According to the team, scientists in Japan and South Korea have pursued research to recreate a mammoth using cloning technology, while scientists in Europe and the United States are experimenting with genome editing technology in the same quest.