The Implications of CRISPR Gene Editing

The Gene Therapy conference held in 1990

The advent of this technology has its adherents and its critics, but what exactly does CRISPR entail, and what does it mean for our world? Gene editing has been engineered since the late 20th century, however, CRISPR itself had only been invented in 2009, and with it came considerable ease in editing an organism’s genome. This gene editing tool can edit a live organism’s genes in vivo by removing a part of DNA or a gene, or replacing it with another component coding for a more desirable trait.   

 The good, the bad and the revolutionary       

CRISPR has yet to be utilized commercially, but there is ambition to administer it in fields such as the engineering of new pharmaceuticals, or in agriculture and pest 

 An example of the mistrust towards the application of genetic modification

These fears are actually not unfounded, as there is an ever-present risk of DNA damage with the use of CRISPR, a threat that one should not take lightly, as this could potentially cause harm to any recipient of this treatment. In fact, CRISPR may induce cancer in organisms subjected to it due to the fact that it activates and inactivates the wrong genes at areas of DNA that are not even close to the edit. This suggests that CRISPR can be a very unpredictable and erratic tool; who knows what could happen to someone who would undergo treatment utilizing it? On top of that, thousands of bases can get deleted from a string of edited DNA. Very worrying indeed. 

  There is also a vested interest to downplay these findings by the companies involved with CRISPR. Within the first 20 minutes of publishing the damning research, the three publicly traded CRISPR companies lost 300 million dollars in value. What really made CRISPR controversial, though, was the whole debacle with genetically modified babies. That in itself led to a whole ethical debate that marred CRISPR for a good while, or more aptly, to this day.

Dr. Jianku and Mr. He

Mice like these were used in the research Dr. He had likely gained his inspiration from

  Dr. Jianku He genetically modified two embryos in vitro that would become two baby girls named Lulu and Nana. What Dr. He was attempting to create were babies that would be immune to HIV, smallpox, and cholera by editing out a gene called CCR5. CCR5 is a gene that encodes the CCR5 protein that is found on the surface of white blood cells; it is involved in the immune system and it acts as a receptor for specific types of signalling proteins called chemokines. The CCR5 protein the CCR5 gene codes for is used by HIV to spread the infection. Deletion of the CCR5 gene however, results in resistance towards HIV infection, as seen among populations with a mutation that results in the aforementioned deletion. No doubt Dr. He observed this phenomenon and applied his knowledge to it. Both Nina and Lulu also would indirectly benefit from heightened cognitive ability due to the deletion of CCR5, as observed in mice. 

  The babies were born, and with that came the backlash against Dr. He. Multiple investigations were opened against him as well as his confidants, and the Chinese government had suspended all of his research activities. This had been an especially painful blow to the Chinese government, especially since it had funded this project. Clearly something had disturbed the scientific community, resulting in irreparable damage to both Dr. He’s reputation and the reputation of CRISPR technology itself. It was far too little too late, as far as He’s punishment was concerned. This ordeal would no doubt  potentially act as a warning to those who would ever attempt a hand at eugenics as Dr. He had done. 

The path to redemption

This is what sickle cell anemia looks like. Notice how the red blood cells are crescent shaped? The phenotype is all but altered indefinitely among two people for whom the treatment was a success.

The attempts to utilize CRISPR for eugenics are a serious concern in the field, as shown. However, there is a somewhat brighter side to all this, in that CRISPR has already been used for less morally dubious means, for a lack of a better term. 

 Three people, two with beta thalassemia and one with sickle cell disease, have already had their genetic diseases treated with CRISPR, after having their bone-marrow stems edited. The subjects no longer require regular blood transfusions after the treatment, making this essentially a functional cure for their diseases. 

The above treatments were done in vitro, meaning a sample was taken of the patient’s bone and altered so that when placed back into the patient, would alter the surrounding cells, and thus would treat the patient. In vitro studies are termed colloquially as “test tube” studies as they occur outside of the natural biological contexts of an organism, which then urges us to pose the question: have we used CRISPR to edit human genes in vivo, or more casually, have we edited genes within people, in the human body itself, so that cells didn’t need to be removed by the body, edited, and replaced in order to administer the treatment? That the treatment can be injected and infused as is?

The answer is that we have. We used CRISPR in vivo to cure hereditary blindness in a person with  Leber congenital amaurosis. Though this is not the first time in vivo gene editing has been administered on humans, this is the first time in vivo gene editing  has been administered on humans using CRISPR, which is still a landmark particularly because of this method’s precision in editing genes, and because the previous method had done little to affect change. This was done by injecting a virus near the photoreceptors of the retina, so that they would infect the photoreceptor cells and edit the genes of those cells, so as to cure them. 

Though it is not known whether the patient was cured of their blindness, especially since the results of the trial have not been reported, this still demonstrates a push towards the development of revolutionary, and at times frightening, technologies. To grant sight is to alter one’s perception of the world, which in turn would alter ours.

Conclusion

Have we the ability to grant the blind sight?

These are  by no means inconsequential feats for modern medicine, and will pave the way for new treatments of debilitating disease, to the point of redefining illness. Clearly we are watching the stuff of fiction unfold before our eyes, when we can alter an individual’s genetic disposition, which is synonymous with their physical being. Could this also redefine how we define ourselves? Will we start evaluating any ailment or perceived flaw as being alterable after a treatment such as this? Who would we be after a defining part of ourselves changes for the rest of our lives?                                                                                                                                                          

Answers to these questions are to be found in the foreseeable future. We will wait and see, bide our time, that is all we can do in the face of our brave new world.

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