But Will It Be a Mammoth?

“The dawn of the era of cloning is a little like splitting the atom, with enormous prospects for evil and enormous prospects for good.”
Glenn Bucher

Ice is central to the story of the Woolly Mammoth. The last ice age drove the evolution of Woolly Mammoths.  One of the driving factors in the extinction of Woolly Mammoths was the loss of ice at the end of the last ice age.  Finally, ice in the form of permafrost might let Woolly Mammoths walk the earth again. Permafrost “is a permanently frozen layer at variable depth below the surface in frigid regions of a planet (such as earth).”  Some permafrost dates to the last ice age. 

The Woolly Mammoth has become the poster child for the cloning of extinct animals. Most of the Woolly Mammoths became extinct around 11,000 years ago at the end of the last ice age. However, a group of Woolly Mammoths survived until about 4000 years ago on Wrangel Island in the arctic ocean.  Rising water separated Wrangle island from the rest of northern Russia around the time the rest of the Mammoths died out. (The Last Wooly Mammoths Died Isolated and Alone)

When some Wooly Mammoths died, they got frozen in the permafrost, which preserved the mammoths. In 2013 Scientists found a 10,000 years old Wooly Mammoth so well preserved it started to bleed when it thawed. (Preserved Woolly Mammoth with flowing blood found for first time, Russian scientists claim)

Preserved mammoth remains have led to scientists thinking that they might clone the Wooly Mammoth. The reason frozen mammoths might make cloning possible is DNA, more specifically the preservation of DNA.  Scientists hope that viable cells or DNA can be derived from the frozen mammoths and used to clone living mammoths.  Currently, scientists are researching three methods to clone the Wooly Mammoth. 

The first technique is nuclear transfer.  In this method, scientists would inject a mammoth nucleus into a host egg, which would give rise to a mammoth embryo.  Second, scientists are hoping to fertilize elephant eggs with mammoth sperm.  The fertilization would produce a half-mammoth half-elephant hybrid.  The hybrids would then be bread together over several generations to create a full mammoth. Lastly, scientists have sequenced the Woolly Mammoth genome.  With this information, scientists plan to use CRISPER to edit mammoth genes into elephant DNA. Scientists would then use the engineered cells to produce mammoths.

So, we have preserved mammoths, that scientists think they can use to clone the Wooly Mammoth. Why would we clone a Wooly Mammoth? There are two fundamental reasons to clone a Wooly Mammoth. One, we can get scientific information about mammoths from the clones. Two, we want to see Wooly Mammoths walking around. These two reasons are not mutually exclusive.

However, there are problems with cloning mammoths for scientific research.  Specifically, the only scientific reason to clone the mammoths is so we can learn something we can’t learn from the genomic sequence. Can any of the three cloning methods teach us how a real mammoth lived? The first method of nuclear transfer cloning doesn’t work. It turns out that mammoth nuclei from a 28,000-year-old mammoth named Yuka were injected into mouse eggs (Signs of biological activities of 28,000-year-old mammoth nuclei in mouse oocytes visualized by live-cell imaging).  Scientists hoped that the mouse eggs would activate the mammoth nuclei and repair the DNA.  The mammoth nuclei did activate, but the DNA repair failed. The scientists concluded, “the results presented here clearly show us again the de facto impossibility to clone the mammoth by current NT technology.”

The second method using mammoth sperm to fertilize an egg will have the same problems as nuclear transfer.  Essentially a sperm cell is simply a way to transfer a nucleus into an egg cell. Even if scientists could get nuclear transfer cloning or sperm fertilization to work, this will not produce a full mammoth. 

To understand why these cloning technics will not produce a full mammoth it’s necessary to understand some cell biology.  All multicellular animals are eukaryotes, and eukaryotic cells contain multiple membrane-bound organelles.  One organelle is the mitochondria, which have DNA and are inherited only from the mother.  Therefore, nuclear transfer or sperm fertilization will not produce mammoth mitochondria. Thus, with these two techniques, the “mammoth” will never have mammoth mitochondria.

That leaves CRISPR mediated genetic engineering.  Using CRISPR, scientists would take a cell and use CRISPR to engineer mammoth genes into the cell.  According to the Woolly Mammoth page on the Revives and Restore project site, the genome of the Woolly Mammoth is 99.96% identical to the Asian elephant.  Mammoth produced by genetic engineering, will be an engineered Asian elephant, there will always be some modern Asian elephant DNA.  While some modern DNA might not seem important, it will be imposable to rule out that modern DNA is affecting the mammoths’ biology.

There is one last problem with cloning a Wooly Mammoth for science.  Even if we clone a Wooly Mammoth, we will not have a prehistoric mammoth.  Mammoths like living elephant relatives were likely intelligent and social creatures.  Modern elephants learn how to be an elephant from the members of their herd.  Since we don’t have any living mammoths, we will produce a mammoth that acts like an elephant.

It is unlikely; we will ever produce a 100% biological mammoth.  Additionally, no matter what we do, we will never produce a mammoth that behaves like a prehistoric mammoth.  Therefore, the only real reason to create a Woolly Mammoth would be to see one walk around.  We should ask ourselves, “Is that a good reason to clone a mammoth?”  Additionally, the first few mammoth embryos would have to be gestated by Asian elephants, which is an endangered species.  Is it justifiable to use Asian elephants to produce mammoths when every Asian elephant birth is vital for their species?

There is a lot of information scientists can learn from the Woolly Mammoth.  I am not convinced scientists can learn anything from a “Woolly Mammoth” clone.  Maybe there is a question I am missing, if there is, I would love to hear it from one of the scientists.  I must admit if I had the opportunity to see a Woolly Mammoth walking around, I probably would.  However, is that a good enough reason to clone one? I can’t help but think a discussion about cloning the Woolly Mammoth would make an excellent addition to a scientific ethics course.

Thanks for Listing to My Musings
The Teaching Cyborg

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