Bleeding Edge Gene Editing: CRISPR

If the four letters that make up an organism’s DNA(Deoxyribonucleic acid) are even subtly altered, it can mean certain death. Numerous methods of editing genetic code have sprung up since the discovery of DNA, each one with the acute danger of creating an erroneous edit. Now, CRISPR(Clustered Regularly Spaced Palindromic Repeats), has emerged and gene editing has changed for the better, becoming easier and safer. CRISPR is revolutionizing the way scientists modify genes and presenting limitless more opportunities to rewrite life.

Genetic engineering isn’t stuff of the future, but the reality of today. Genetic engineering has already hugely altered the way people live. CRISPR allows even more control of living things. One example of a result of research in recoding life is the advancement in curing genetic diseases. Daniel Anderson, a bioengineer from the Massachusetts Institute of Technology in Cambridge and his colleagues used Cas9 genes from CRISPR in mice to correct a flaw in the mice’s genes that caused a metabolic disease called tyrosinemia(Ledford 21). A major roadblock in gene editing is making a mistake. These mistakes, no matter how small, can cause cancer and other terminal illnesses. Crops and animals on the farm are also a focus of genetic modification. The US Department of Agriculture has begun to look for improved regulation of GMO crops. In light of CRISPR, the agency knows it must re-evaluate its rules(Ledford 22). CRISPR has the possibility of changing the genes so precisely, new rules must be made to keep the modifications in check. Scientists have been able to engineer many different types of organisms, but some of the most momentous achievements include the advent of synthetic drugs that include insulin, human growth hormone(HGH), interferon, and bovine growth hormone(BGH)(Newton). These drugs and hormones, which were previously extremely scarce or impossible to attain, have revolutionized healthcare. Beyond uses in rich countries, genetic engineering can help countries staggered by war, natural disasters, or famine get back on their feet. The first transgenic cow, Rosie, had human genes embedded into her cow genome. The milk that she produced was more similar to human milk than normal bovine milk; consequently, the milk contained more protein than normal milk. Cows like Rosie can make a huge impact in poor countries where people suffer from malnutrition(Newton). Genetic engineering has an impact in nearly all sectors of the world and CRISPR can advance it far beyond the limits of people's’ imagination. Other definite uses of CRISPR include to create the “cure of otherwise intractable diseases, a vastly more efficient system of food production, the more economical production of medicines, and other improvements to the world’s way of life”(Newton). Control over how living cells work has allowed scientists to do impossible things that seem like science-fiction. Genetic engineering has already done so much for humanity, even with massive barriers in research. Now, CRISPR is rocketing past these barriers with nearly limitless potential.

CRISPR is a revolutionary new way to edit genes, but how and where did it come from? CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats. It refers to palindromic repeats of DNA in a bacteria’s genome. They are interspaced between sets of harmless viral DNA. Although they appear seemingly unimportant, they are crucial to the immune system of bacteria, which unlike ours, can be passed down from generation to generation(“CRISPR”). For example, this system activates when a virus attempts to infect a bacterial cell. When a bacterium is attacked by a virus, the virus inserts some of its DNA into the bacteria’s nucleus. Once the bits of viral DNA have been injected into the chromosome of the cell, the cell’s system creates a molecule called RNA(Ribonucleic Acid), which is an exact replicate of the viral DNA. RNA is extremely similar to DNA, allowing it to interact with DNA(Doudna). This RNA copy of the virus begins to collate with the other essential parts to carry out the next step of the process. As crRNA(CRISPR RNA) from the Cas DNA system in the genome and tracrRNA that’s a copy of the virus’s DNA bind, they change into a complex called the Cas9 protein. The Cas9 protein searches through the DNA of the bacteria until the sequence of DNA matches that of the RNA that is bound to the protein Cas9. When the site is found, the protein uses it’s pair of molecular scissors to cut up the viral DNA. The complex is essentially a guided scissor that can cut the 2 strands of the double helix in DNA(Doudna). This system opens up a spot for the newly introduced DNA can bind. At this location in the bacteria, it’s harmless and instead creates a memory of the virus for the bacteria and its progeny. Those are CRISPR’s origins, however, “scientists have learned how to harness CRISPR technology in the lab to make precise changes in the genes of organisms as diverse as fruit flies, fish, mice, plants and even human cells”(“CRISPR”). From being discovered in bacteria, to being used in labs across the world, CRISPR will revolutionize genetic engineering with its natural and precise process.

CRISPR’s ability to edit genes with unprecedented precision is opening the door to a plethora of uses in the future. In the near future, diseases may finally be on their knees with CRISPR. The Zika DNA vaccine being tested among other DNA vaccines contains genetic material from the virus, once injected into the muscle causes the body to create an immune response to the virus(Mullin). Although this may seem far-fetch after realizing the numerous groups of scientists have tried and ultimately failed trying to create a vaccine for Zika, it is undoubtedly true. “In a call with reporters on [March 31, 2017], [Anthony] Fauci [immunologist] said initial results in 40 volunteers indicate that the vaccine produced an immune response against Zika and didn’t cause serious side effects”(Mullin). Along with other a vaccine for Zika, the method’s flexibility allows other vaccines to be created as well. For example, “the NIH [National Institutes of Health] has created a DNA vaccine against West Nile Virus, although it was never commercialized”(Mullin). Even though this is a huge achievement in healthcare, the future of CRISPR extends far beyond the obvious. CRISPR’s precise gene editing capabilities allow the modification of genes that can proliferate rapidly through a population. In other words, it has the potential to eradicate a whole population of mosquitoes that could carry disease(Ledford 24). In the near future, the world’s greatest killer, disease carrying mosquitos, may finally be vanquished under the power of CRISPR. The future of CRISPR will bring an end to many devastating illnesses while bringing in new technologies to make lives more comfortable.

Rewriting life has been a key interest in the science community on account of learning about DNA, but with CRISPR, people can change genes with unprecedented precision. The future rests in programming, whether it be computers or life. With CRISPR, doctors can correct birth defects, get rid of problematic genetic disorders, and cure otherwise incurable diseases. As new improvements are discovered every day CRISPR will solve problems society never thought solvable; changing the world forever.

  1. "CRISPR: A game-changing genetic engineering technique." Science in the News. Harvard University, 31 July 2014. Web. 03 Apr. 2017. < http://sitn.hms.harvard.edu/flash/2014/crispr-a-game-changing-genetic-engineering-technique/>.
  2. Doudna, Jennifer. "Jennifer Doudna: How CRISPR lets us edit our DNA." TED. Web. 6 Apr. 2017. < https://www.ted.com/talks/jennifer_doudna_we_can_now_edit_our_dna_but_let_s_do_it_wisely/transcript?language=en>.
  3. Ledford, Heidi. "CRISPR, the disruptor." Nature 522.7554 (2015): 20-24. Web.
  4. Mullin, Emily. "U.S. government moves forward with tests of novel Zika vaccine." MIT Technology Review. MIT Technology Review, 03 Apr. 2017. Web. 03 Apr. 2017. < https://www.technologyreview.com/s/604036/us-government-moves-forward-with-tests-of-novel-zika-vaccine/>.
  5. Newton, David E. "Genetic Engineering." Issues: Understanding Controversy and Society, ABC-CLIO, 2017, issues.abc-clio.com/Search/Display/1097973. Accessed 30 Mar. 2017.