Though the ethical concerns of gene editing and similar practices have existed since the concept first emerged decades ago, new discussions have arisen with the CRISPR-Cas9 technique. CRISPR-Cas9 is used to cut DNA at a particular, targeted location. The complex made up of Cas9 and guide RNA can find a targeted section and cut it. If it works, the cell will repair the double cut, and replace it with a non-mutated form of the gene. With more development, it can be used to remove the genes for severe diseases such as sickle cell anemia or cystic fibrosis. Though the technology offers promising results, it is currently unsafe and has the potential to be unethical. Currently, there is much more testing that needs to be done before the technology can be safely used in humans. There are concerns with the successfully edited cells being more likely to cause cancer, as well as moral concerns about the fine line between saving lives and genetic enhancement. Thirdly, scientists are not entirely sure that the technique is effective enough to help humans just yet.
Since the method is so new, extensive research is still required before it can be tested in humans, and there are specific concerns with tumor antigen p53. The scientific community considers CRISPR-Cas9 not completely understood (Weintraub, 2018). CRISPR-Cas9 is not completely effective, due to its interactions with gene p53, which plays an important role in tumor prevention. It also acts as a defense mechanism to CRISPR-Cas9, causing an edited cell to self-destruct and lowering the success rate of the gene editing method. When the edit works correctly, that could mean that p53 isn’t functioning properly. A malfunctioning p53 has been linked to many types of cancers. (Ihry et al., 2018). If cells that have been successfully edited are have malfunctioning p53, it could have a long-lasting effect (Haapieniemi et al., 2018). Genes edited with CRISPR-Cas9 are potentially passed down from generation to generation (Weintraub, 2018). With the technology still being so new, there is also room for error in the guide RNA. Multiple studies demonstrated the significant rate of off-target mutations in mammalian cells, which occasionally surpassed mutagenesis, meaning it resulted in noticeable changes to the DNA (Gupta, 2014). Effectively, the targeting specificity necessary to be safe for humans is not there yet. In March, the World Health Organization agreed that human germline genome editing is “irresponsible at this time” for these very reasons.
Furthermore, it’s important to differentiate between genetic enhancement and saving lives. It’s relevant in the He Jiankui case and in general begs the question: how far is too far? He Jiankui focused on targeting the CCR5 gene to make the twins immune to HIV. However, the lack of CCR5 can make a person more susceptible to infections like the flu. It is still widely unknown whether the twins really have added protection, or if there were more unintended edits. The removal of CCR5 was also shown to boost visual and spatial memory (Weintraub, 2018). Editing genes to remove a virus that can be completely controlled with medication, as well as improving the girls’ memories, purposefully or not, is closer to designer babies than it is a medical breakthrough. Given no legal framework, it is likely that the gene-editing nprocess could be taken too far. Medical technology should be used to save lives, and help those with life-threatening diseases, as opposed to creating genetically superior babies. Moreover, this leads to societal issues in that a family with more money could potentially cure their child with the CRISPR-Cas9 technique when a family who didn’t have the money could not. There comes a point where society must determine how loving parents are to handle this cutting edge technology.
Lastly, the word that comes up so frequently when the scientific community is asked about the CRISPR technologies is “uncertainty.” There is specific uncertainty when it comes to the success rate of the method. The three major concerns here are the editing efficiency, incomplete editing, and the aforementioned off-target editing. These concerns could become obsolete with more years of research, but at this point in time the risk seems to outweigh the benefit. It is still unknown if modified organisms are affected for their whole lives. The potential passing on of editing genes could lead to unexpected effects. Since it’s so difficult to understand the future of CRISPR-Cas9 organisms, it makes it even harder to make a moral decision using risk-benefit analysis (Brokowski and Adli, 2019). In a situation with so many unknown factors, there’s not much of an argument for the use of this technology in embryos thus far. Yet another unsolved obstacle for CRISPR-Cas9 is that designing a phenotype is much more complex than just changing a single gene, because traits are determined from a multitude of genes, making some changes unpredictable (Brokowski and Adli, 2019).
In conclusion, the CRISPR-Cas9 editing technique is too new and too unknown to be used in humans, and will require a lot more research to become both safe and ethical. Studies have shown that it raises the likelihood for cancer. Even worse than the known possibilities are the unknown ones: the potentials for mosaicism, the lack of long term effects, and the effects of off-target editing, amongst others. At this point in time, the CRISPR-Cas9 technology has great potential, but it currently unsafe as well as unethical because the risk outweighs the benefit. Down the road it could save lives, but the difference between that and designer babies needs to be understood.
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