By Camila Aragón Alfaro
Introduction
When the Chinese biophysicist He Jiankui announced in 2018 that he had managed to successfully produce two genetically edited newborn babies, both the scientific community and the general public were outraged—He’s actions represented a blatant violation of bioethics and introduced a scary reality into our world. He modified a key gene in some human embryos to confer resistance to HIV using an up-and-coming technology known as CRISPR, forged ethical review documents, and misled doctors into implanting the embryos, leading to the first-ever genetically engineered babies. A court in Shenzhen ruled that He and his collaborators had violated national regulations on biomedical research and medical ethics, and He was sentenced to 3 years in prison (Normile). But He’s research had already left irreparable effects in the field of gene engineering and tarnished the name of CRISPR: the idea of “designer babies” had become a major public concern.
What Is CRISPR?
CRISPR stands for Clustered Regularly Interspaced Short Palindromic Repeats and consists of repetitive DNA sequences. These were originally observed in bacteria with “spacer” DNA sequences between these repeated sections that matched viral sequences. It was then discovered that, upon viral infection, bacteria copy their DNA to make RNA (in a process known as transcription), the latter which guides CRISPR-associated nucleases, or Cas protein (which is why this editing technique can also be referred to as CRISPR/Cas), to cut viral DNA and provide protection against the infection (Bettridge, The Jackson Laboratory).
The discovery that the transcribed RNAs can be modified to guide a Cas nuclease and can be made specific to target only one sequence, provides an extremely powerful gene editing tool that could cut specific parts of a DNA sequence (The Jackson Laboratory). CRISPR was on the rise to establish itself as a groundbreaking technique that further testing proved effective in human cells and, in 2020, earned CRISPR pioneers Jennifer Doudna and Emmanuelle Charpentier the Nobel Prize in Chemistry (NobelPrize.org).
A Cas9 protein in action targeting a DNA strand (Source: Meier and Reifsnyder).
The Concern
Currently, CRISPR-Cas is being used in research laboratories all over the world for multiple purposes, but their research is different from He Jiankui’s infamous experiment in one crucial aspect: the type of cells being targeted. CRISPR-Cas was designed to be used to modify our somatic cells, which are the cells that make up our body that are not of reproductive nature. He’s experiment, however, sought to edit the genome of early embryos, which, alongside the editing of the genome of gametes (our reproductive cells, either eggs or sperm) is a type of gene editing known as germline editing. Unlike the editing of somatic cells, editing reproductive cells has the potential to not only affect the individual, but also their progeny, and can be theoretically used to enhance desirable traits instead of seeking to cure diseases (The Jackson Laboratory). And this can lead to very dangerous territory.
The most evident danger of germline editing is its potential to affect the individual’s progeny—which can have unpredictable consequences for future generations. In edited embryos, the Cas nuclease might fail to cut both copies of the target gene, or the cell can begin dividing before the corrections have been made, resulting in no guarantee of the effectiveness of the technique or this type of editing’s ability to produce safe modifications (Lanphier et al., 410–411).
The second major concern regarding germline editing is its potential to “fix” things that do not need to be fixed—that is, its ability to possibly modify traits rather than treat diseases. This is of special concern to individuals considered to be “genetically inferior”, as they fear this technique might be exploited to delete them from existence. Disabled individuals are no strangers to the societal view that genetic differences, rather than being seen as an intrinsic aspect of the diversity of the human species, are seen as defects that should be corrected—and a tool that can do just that could pose an existential threat to this group of individuals (Sufian & Garland-Thomson, Marshall). Further, the possibility of germline editing raises concerns over the eventual development of “designer babies”—babies genetically altered for the sole purpose of giving them desirable traits. This concept raises concerns about the possible creation of a “superhuman” race. Another worry is the possibility of being able to select the baby’s sex, which becomes especially troubling in cultures that have historically deemed a certain sex more desirable (Farr).
Why We Shouldn’t Fear CRISPR
Truth is, the majority of concerns regarding the use of CRISPR arise from the fact that people don’t fully understand how gene editing works, and the media sensationalizing and stoking public fear of CRISPR (Creighton). The general population has the misconception that the days of creating so-called “designer babies” lurk right around the corner—which is not true for many reasons.
To begin with, it is very unlikely that we will be able to select certain genetic traits. The CRISPR/Cas method has a defining limitation: the technology can only cut DNA. This means that the organism has to either rely on existing proteins in the cell or introduce engineered ones, to help repair or modify the DNA after it’s cut. Without the right proteins to ensure successful gene expression, even if the DNA is edited, the desired traits may not appear. This limits the availability and effectiveness of the technology (Bettridge). Additionally, there is limited knowledge regarding the genes responsible for physical and personality traits commonly associated with designer babies, such as intelligence, height, or athleticism, which are influenced by multiple genes that are unable to all be controlled at once (Witkowsky). For example, scientists have tried to search for a single gene linked to intelligence—but the gene with the strongest effect only raises IQ by about 1 point (Klitzman). Without fully understanding how to drive the expression of these complex traits, we cannot reliably engineer such characteristics in humans.
Furthermore, the rise of gene editing has already led to multiple regulations. For instance, there already is the Universal Declaration on the Human Genome and Human Rights, which seeks to protect and preserve the human genome, and the Oviedo Convention, which states that genetic modifications can only be done for “preventive, diagnostic, or therapeutic purposes” (Creighton). In Western Europe, 15 out of 22 countries prohibit germline modifications, and the US National Institutes of Health’s Recombinant DNA Advisory Committee explicitly states that it will not consider proposals for germline modifications (Lanphier et al., 410–411). CRISPR/Cas is also a very difficult technique that only the highest trained scientists can do, and even then, they require the assistance of multiple experts outside their field of study—so “rogue mad scientists” are unlikely to abuse this technology.
This is also not the first time the general public has been alarmed by the possible dangers of scientific leaps and “slippery slopes.” In 1970, the rise of amniocentesis (a form of prenatal genetic screening) alarmed many, fearing its potential use for eugenics—which did not happen. Preimplantation genetic diagnosis, which arose in the 1980s and 1990s, consists of performing a biopsy on an IVF-created embryo to identify traits that could result in life-threatening conditions—and it was also petitioned to be prohibited in fear that people would rush to do IVF just to have the possibility to screen their embryo for trivial things (Frellick). Actually, in-vitro fertilization itself was once as controversial as CRISPR is today. In 1972, the British magazine Nova published a cover story arguing that test-tube babies were “the biggest threat since the atomic bomb”, and the American Medical Association advocated for stopping research involving “human fetal tissue” (CBC Radio). Nowadays, IVF is a widespread procedure that has led to millions of births—and none of the initial fears have come true.
Moving Forward
Despite the sensationalism and exaggerated fears often portrayed in the media, CRISPR/Cas is not the catastrophic threat it is sometimes made out to be. While it is impossible to deny its potential risks and ethical concerns, the benefits and possibilities for medical and scientific advancement are immense. CRISPR holds the potential to unlock treatments for diseases once thought incurable, from genetic disorders like cystic fibrosis to devastating conditions like cancer. With each breakthrough, we move closer to a future where gene editing can heal at the source, transforming lives and rewriting the possibilities of medicine.
We must place our trust in the scientific community, allowing progress to flourish rather than letting fear hold us back. As we stand on the brink of groundbreaking advancements like CRISPR, it is our responsibility to educate ourselves, engage in informed discussions, and support innovation that can change lives for the better. Embracing and responsibly advancing such technologies can lead to significant breakthroughs, and it is essential to approach these developments with a balanced perspective that fosters innovation rather than stifles it.
Will we end up having superhuman designer babies? It is very unlikely: human traits are shaped by complexities we can't simply engineer. The real challenge, though, isn't just what we can or cannot create—but what we should.
Works Cited
Bettridge, Kelsey. “CRISPR: Facts, Myths, and How to Engage the Public.” Biophysical Society Blog, 7 Sep. 2018, https://www.biophysics.org/blog/crispr-facts-myths-and-how-to-engage-the-public
“Canadian scientists fear blowback over CRISPR babies could undermine their work.” CBC, 7 Dec. 2018, https://www.cbc.ca/radio/day6/episode-419-pot-jobs-in-alberta-p-is-for-pterodactyl-the-impeach-o-meter-crispr-for-good-and-more-1.4934721/canadian-scientists-fear-blowback-over-crispr-babies-could-undermine-their-work-1.4934732
Creighton, Jolene. “The Age of CRISPR: Why You Shouldn't Fear Gene Editing.” Futurism, 23 May 2016, https://futurism.com/the-age-of-crispr-why-you-shouldnt-fear-gene-editing
Farr, Christina. “Some families are paying thousands of dollars to choose their baby’s sex.” CNBC, 4 Aug. 2018, https://www.cnbc.com/2018/08/04/fertility-clinics-advertise-gender-selection-ethical-wuandary.html
Frellick, Marcia. “Bioethicist: History Tells Us CRISPR Fears Are Overblown.” Medscape,1 Nov. 2017, https://www.medscape.com/viewarticle/888032?form=fpf
Klitzman, Robert. “Designer babies are on the way. We’re not ready.” CNN, 16 Aug. 2019, https://www.cnn.com/2019/08/16/opinions/gene-edit-dangers-opinion-klitzman/index.html
Lanphier, Edward, et al. “Don’t edit the human germline.” Nature, vol. 519, Mar. 2015, pp. 410–411, https://www.nature.com/articles/519410a
Marshall, Lisa. “Why This Disability Activist Fears CRISPR.” WebMD, 11 May 2021, https://www.webmd.com/children/story/centerpiece-crispr-sidebar
Normile, Dennis. “Chinese scientist who produced genetically altered babies sentenced to 3 years in jail.” Science, 30 Dec. 2019, https://www.science.org/content/article/chinese-scientist-who-produced-genetically-altered-babies-sentenced-3-years-jail
“Press release”. NobelPrize.org, 22 May 2024. https://www.nobelprize.org/prizes/chemistry/2020/press-release/
Sufian, Sandy, and Rosemarie Garland-Thomson. “The Dark Side of CRISPR.” Scientific American, 16 Feb. 2021. https://www.scientificamerican.com/article/the-dark-side-of-crispr/
Wanner, Mark. “CRISPR/Cas9: A natural mechanism goes to work.” The Jackson Laboratory. https://www.jax.org/news-and-insights/2015/july/how-does-crispr-work
“What is CRISPR?” The Jackson Laboratory. https://www.jax.org/personalized-medicine/precision-medicine-and-you/what-is-crispr#
Witkowsky, Lea. “The Designer Baby Distraction.” American Society for Microbiology. https://asm.org/articles/cultures-magazine/volume-4,-issue-4-2017/the-designer-baby-distraction
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