Over the past few years gene-editing and CRISPR, in particular, has been a topic of interest to many. The very thing that will revolutionize our very own world. Just the idea of it is mind-blowing 🤯
Scientists are still in the early stages of figuring out this technology. The ability to alter DNA-the code for life- could have huge applications such as resurrecting endangered species. Jurassic Park imagined a future in which it was possible to bring dinosaurs back to life. Now, that fiction may become a reality!
In order to understand how this is possible, we first need to go over CRISPR
CRISPR Crash Course
In essence, CRISPR is a technique that allows scientists to make precision edits to any DNA, whether bacterial or human. CRISPRs are a special kind of repeating DNA sequence that bacteria have as part of their immune system. Bacterias use these genetic sequences to “remember” each specific virus that attacks them. They do this by incorporating the virus’ DNA into their own bacterial genome. This viral DNA ends up as the spacers in the CRISPR sequence. Then the Bacteria can use CRISPR/Cas9(a protein) to cut up the DNA of invading bacterial viruses that might otherwise kill them.
Now, the interesting part is that we can actually use this molecular machinery for an entirely different purpose — to change any chosen letters in an organism’s DNA code! Edit the very code of life.🤯
How CRISPR Can Revive Animals
Crispr has been discussed as a de-extinction tool since its earliest days. However, in order to de-extinct something you must understand and know the species genome. A genome is the genetic material of an organism. It consists of all its DNA. One very interesting individual, George Church, a geneticist at Harvard Medical School has set out to revive the woolly mammoth.
De-extinction of The Woolly Mammoth
The first step in de-extinction like I mentioned above is mapping its genome. The woolly mammoth has so far been partially mapped from ancient bones and other remains. Armed with that information, it's possible to use Crispr to edit DNA from the Asian elephant, the mammoth’s closest living relative. By cutting and pasting DNA, the Asian elephant can inherit the characteristics of the woolly mammoth such as long fur, thick layers of fat and its behavioural traits. By synthesizing the genes, placing them into the embryo of an Asian elephant, then putting the embryo back into an Asian elephant, the elephant can give birth to a woolly mammoth. However, the technology isn’t completely there yet. Research is still being conducted and de-extinction may be possible in the next few years.
Future Steps For The Woolly Mammoth Project
Improving the Genome: With the completion and publication of multiple fully sequenced Woolly Mammoth genomes, the Church lab is discovering potential cold climate adaptations in different genes. The Woolly Mammoth and Asian Elephant genomes are different by ~1.4 million mutations, meaning an Asian Elephant is already 99.96% Woolly Mammoth. Of those ~1.4 million mutations, 2,020 are mutations that change 1,642 genes (~6.5% of all genes in the genome). The Church Lab is currently analyzing mutations in DNA regions that regulate the expression of genes. As important genes are identified for de-extinction, the researchers can attempt to edit them into the Woolly Mammoth cell lines growing at the Church Lab.
Embryos: Once Woolly Mammoth-like traits appear sufficiently in stem cell-derived tissues, the begin experiments to generate embryos, possibly through stem cell embryogenesis. A plan to construct artificial(uterus) parts to gestate the embryos. If this is done we would no longer need the Asian elephants as mothers. This may seem like science fiction at first. But it is completely possible. In fact, 2 breakthroughs:1) the birth of mouse pups from 3D printed ovaries, and 2) the growth of fetal lambs transferred to an artificial uterus partway through pregnancy, show how it’s possible to generate an artificial uterus.
What Does This Mean For Us?
One of the reasons why scientists want to revive the woolly mammoth, in particular, is because of its ability to combat global warming.
Arctic lands are covered by areas of ground known as permafrost that have been frozen for ages. Permafrost acts as a carbon sink, containing vast amounts of carbon from dead plant life that is locked away by the extremely cold temperatures. The amount of carbon in these frozen stores is estimated to be about twice as much as that currently in the atmosphere. If it thaws out, microbes will break down soil organic material to release carbon dioxide and methane into the atmosphere.
This is where our friend the woolly mammoth comes in. Large mammoths kept the mammoth steppe, one of the world’s most expansive ecosystems in check by knocking down and trampling trees, allowing only grass to grow in its place. This helps because grass absorbs less sunlight than trees, this would cause the ground to absorb less heat and in turn, keep the carbon pools and their greenhouse gases on ice for longer. In this way, the mammoths inadvertently acted as natural geoengineers. However, the only problem is around 17000 of these mammoths would be needed to stop the ice from thawing out. Regardless, its a step in the right direction.
- Gene editing could be the next big thing and has many implications
- CRISPR is a technique that allows scientists to make precision edits to any DNA
- Different species can gain characteristics of another species, by cutting and pasting the DNA
- De-extinction of certain species like the woolly mammoth is possible through this technology
If you enjoyed reading this article, please press the👏 button, and follow me to stay updated on my future articles. Also, feel free to share this article with others!
Follow me on Medium and LinkedIn to stay updated!