The mammoth may be coming back, but not this decade

Great article, albeit ridden with terrible puns.

I am a former cell biologist and have spent the last two years researching and writing about de-extinction, the science of bringing extinct animals back to life. I have spoken with Church, as well as many of the other scientists at the forefront of de-extinction research, and two things are clear to me. The first is that a living, breathing woolly mammoth is far from imminent, and the second is that, nevertheless, the science needed to make it is progressing at quite a lick.

The first thing to bear in mind is that Church is not talking about making a living, breathing, fur-coated mammoth calf. His work so far focuses solely on single cells... Church's team have made 45 changes to the elephant genome. They are moving closer to their goal of "mammoth-ifying" an elephant cell. Church argues that he does not need to put every single tweak into his elephant cells to make something mammoth-like.

Church has never claimed that he is making a bona-fide, genuine, 100% authentic woolly mammoth. Instead it will be an animal whose DNA is largely elephant, but with a smattering of judiciously-placed mammoth DNA. He talks of making a "mammoth-elephant hybrid" or a "cold-adapted elephant". I prefer to call it a "mammophant" or "elemoth".

Assuming Church manages to create a mammophant cell, the next step will be to convert it into a mammophant embryo... It is a mammoth task (sorry about that) but it is not impossible. However, even if Church pulls it off, he will still need to find a way to nourish the embryo while it grows.

The elephant eggs needed for cloning need not come from the reproductive systems of living elephants. There are other ways to make them. Animal studies have shown that skin cells can be reprogrammed in a dish to make stem cells, which can then be coaxed to form eggs. It is almost like cellular alchemy. Rather than performing invasive surgery to retrieve eggs from adult female elephants, it should be possible to make them from non-invasive skin biopsies.

Once the embryos have been made, they could be nurtured, not in adult animals, but in "artificial wombs". This may sound like the stuff of science fiction, but Church and other researchers are quietly developing the science needed to make it happen. He explained last week that researchers in his lab have grown a mouse embryo in an artificial womb for 10 days; halfway through its normal gestation period.

At this point it should be clear that de-extinction is profoundly difficult, and that we are not going to have any living mammoths roaming the Siberian tundra in the next few years. But at the same time, it seems likely that if scientists like Church keep pushing, they will get there eventually. The bigger question is: should we do it? What would be the point?

For me, the single biggest argument in favour of resurrecting extinct species is the beneficial spin-offs it will create for endangered living species. The same techniques being used to bring back extinct animals – stem cell technology, genome sequencing and editing, and assisted reproduction techniques such as cloning – can be used, far more easily, on threatened living species.


http://www.bbc.com/earth/story/20170221-reviving-woolly-mammoths-will-take-more-than-two-years