Scientist Who Cloned Dolly Points to Possible Ways to Clone Mammoth

After Russian scientists announced the unearthing of an adult female mammoth preserved so well that her muscle tissue still clung to her carcass, talk of cloning her was quick to follow. However, while he doubts that the massive and ancient creature could ever be cloned the same way his team went about cloning the famous sheep Dolly, Ian Wilmut, an emeritus professor at the University of Edinburgh, argues that other possibilities may remain.

In order for a clone like Dolly to be born, Wilmut argues that females of a closely related species is needed in order to provide unfertilized eggs and, in the case that this phase is successful and embryos are created, carry out the pregnancy.

"Cloning depends on having two cells," Wilmur writes in an essay published on the academic journalism website The Conservation. "One is an egg recovered from an animal around the time when usually she would be mated."

Furthermore, the scientist points out, cloning is an inefficient process with a success rate of 5 percent at best.

Still, Wilmur says he hasn't given up on the idea entirely.

"Even if the Dolly method is not possible, there are other ways in which it would be biologically interesting to work with viable mammoth cells if they can be found," he continues.

In response to the suggestion of using elephant eggs to carry out the procedure, Wilmur argues that, given that the animal already faces the danger of becoming extinct as it is, any kind of experiment that would attempt to take as many as 500 eggs from it "is clearly not appropriate."

"But," he writes, "there is an alternative."

For example, by transplanting ovarian tissue from elephants to mice -- a feat pioneered back in the late 1990s -- researchers could perhaps get their needed elephant eggs yet in the case that the tissue is taken from elephants that die.

Even if this were carried out, however, Wilmur continues on to point out a host of other issues, such as the damage inevitably caused to mammoth cells when allowed to thaw. Freeze-dried cells aren't perfect either, he argues, as seen in research performed in 2008 in which a team of researchers found that when nuclei from freeze-dried sheep cells were transferred into eggs, some developed for a few days, but none to term.

To circumvent these issues, the researcher offers yet another solution: stem cells.

In several species, he points out, it is possible to produce stem cells simply by introducing four selected proteins to give adult cells the same characteristics of embryo stem cells.

These four factors, he explains, give embryo stem cells their unique characteristics and in a 2006 study were found capable of imposing these traits on skin cells. And since this type of stem cell can be grown for extended periods in the laboratory while retaining the ability to form all of the tissues of the body, Wilmur argues it could give researchers a chance to compare mammoth cells with those of elephants.

"This knowledge would be of fundamental biological interest. It would enable us to begin to answer groundbreaking questions. What are the differences between the cells and tissues of these species? What are the similarities? The mammoth lived in a different climate, so was the metabolism of their cells different? Does this information cast any light on the cause of extinction of mammoths?"

In the end, however, the scientist cautions that the welfare of any kind of animal produced during such research ought to be of preeminent concern.

"It would be essential to provide mother and clone with the appropriate environment of temperature, moisture and diet," he argues. "It would almost certainly be necessary to keep the animals in captivity, so it would be essential to provide as interesting an environment as possible. Ideally this should include other elephants, mammoths or hybrids to provide social interaction for the animal."

For these reasons, Wilmur ultimately deems the development of some form of a mammoth unlikely at present -- though, he argues, this could change as science continues to expand.