In a bid to ultimately bring back the woolly mammoth, researchers have inserted some of its DNA into elephant cells grown in the lab, LiveScience reports.
Harvard Medical School's George Church tells The Sunday Times that his team used the CRISPR gene editing tool to insert 14 mammoth genes linked to cold resistance into elephant cells.
"We prioritized genes associated with cold resistance including hairiness, ear size, subcutaneous fat, and, especially, hemoglobin," Church says. "We now have functioning elephant cells with mammoth DNA in them."
Church adds that the work hasn't been published in a peer-reviewed journal yet as they have more to do.
Popular Science notes that the next steps would be to grow these mammoth-elephant cells into specialized tissues to see whether the proper traits are produced before even attempting to grow them in an artificial womb. Even then, it adds, researchers would likely first produce a cold-tolerant elephant, before attempting to insert a greater number of mammoth genes into the elephant genome to create a mammoth.
Others, though, suggest focusing these energies instead on protecting living elephant. "We face the potential extinction of African and Asian elephants. Why bring back another elephantid from extinction when we cannot even keep the ones that are not extinct around? " Alex Greenwood tells the Sunday Times.
Other organisms like the passenger pigeon and saber-toothed cat have also been identified as possible candidates for de-extinction.