Researchers in Japan have taken a step toward bringing back the woolly mammoth, which went extinct following the last Ice Age, the Telegraph reports.
In recent years, scientists have pondered whether certain species could undergo "de-extinction" and be resurrected. In particular, researchers have bandied about bringing back not only woolly mammoths, but also passenger pigeons and saber-toothed cats. In 2015, Harvard Medical School's George Church told the Sunday Times that he and his team had used CRISPR to insert 14 cold resistance genes from mammoths into elephant cells and that the resulting cells were functional.
Researchers led by Akira Iritani from Kindai University now report additional progress toward de-extinction. They isolated nuclei from a 28,000-year-old woolly mammoth called Yuka that had been recovered from permafrost in Siberia. As they write in Scientific Reports this week, they transferred those nuclei into living mouse oocytes and a portion of those then appeared to have biological activity, including spindle formation.
"Yuka's cell nuclei were more damaged than we thought, and it would be difficult to resurrect a mammoth as things stand," author Kei Miyamoto, a lecturer in developmental biology at Kindai, tells the Japan Times. "There's a chance, if we can obtain better-preserved nuclei."