Harvard Medical School's George Church says he is only a few years away from developing a woolly mammoth-elephant hybrid, New Scientist reports. A pure woolly mammoth, he notes, will take even longer.
Church has discussed the "de-extinction" of the woolly mammoth for quite some time, and has been working on splicing woolly mammoth genes into the Asian elephant genome. Last year, he told Live Science that his lab had used the CRISPR gene-editing tool to insert more than a dozen mammoth genes into elephant cells. Those genes including ones associated with cold tolerance like hairiness, hemoglobin, and subcutaneous fat.
Now, Church says that they've made 45 mammoth-like edits to the elephant genome. He adds that the next step would be to develop a hybrid embryo from these cells, noting that it would mostly be an elephant with some mammoth characteristics, New Scientist reports. "We're not there yet, but it could happen in a couple of years," he says.
Since Asian elephants are endangered, New Scientist notes Church hopes to grow any woolly mammoth fetus in an artificial womb. The Guardian adds that his lab has had some success in gestating mice that way in the lab.
The attempt, the Guardian notes, raises a number of ethical concerns. "The proposed 'de-extinction' of mammoths raises a massive ethical issue — the mammoth was not simply a set of genes, it was a social animal, as is the modern Asian elephant," the University of Manchester's Matthew Cobb tells the Guardian. "What will happen when the elephant-mammoth hybrid is born? How will it be greeted by elephants?"