In October of 2018, the scientific world as we knew it completely changed with the birth of two little girls named Lulu and Nana1. These twins were revolutionary “designer babies” – the first human beings to have each cell of their body genetically modified for certain characteristics [1]. 

Before we go into Lulu and Nana’s story, we have to understand what designer babies are and how they came to be. Designer babies originate from genetically modified embryos prior to implantation through in-vitro fertilization (IVF). Known as human germline genome editing, this gives the power to control the traits children have in the future [2]. Techniques to alter the genetic material of the living have been theorized since the 1970s [3]. However, it was the discovery of a system named Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) in 2012 that resulted in the drastic growth of this field [3]. 

Essentially, CRISPR refers to identifiable groups of short repeated sequences of DNA that are found in microorganism and bacterial genomes [4]. These sequences are integral in the immune systems of these organisms and have now been adapted for genetic engineering [4]. This process begins with identifying target sequences of DNA responsible for coding for a particular trait of interest in an individual. Then, the target sequence needs to be removed from the DNA strand.  The enzyme Cas9 (CRISPR-associated protein 9) nuclease is responsible for splitting the series of nucleotides – or building blocks – in the DNA at very exact locations to extract the target sequence, but Cas9 needs some help to get to the right sequence [5]. This is where, scientists design and make short RNA molecules which act as blueprints to guide Cas9 to remove the target sequence while introducing CRISPR to the new binding sites in the DNA sequence [5]. Here, CRISPR can silence the gene, edit the gene sequence, or even replace a mutant gene with the correct one5. This tool is similar to the “find and replace” function on a document writing software. In a nutshell, CRISPR finds a section of a cell’s DNA that we want to delete, cuts it, removes it, and replaces it with another desirable DNA sequence [6]. This is the fundamental basis behind designer babies. The aim was to genetically modify human embryos using CRISPR to remove genes with the capability to cause diseases like cardiovascular disease, HIV, cancer, dementia and other widespread diseases in the future [7].  

The births of Lulu and Nana in China were the first instances of this seemingly far-fetched idea being put into action. The man responsible was a scientist named Dr. Jiankui He [8]. During the 2018 World Summit of Human Gene Editing, in Hong Kong, on November 25, 2018, Dr. He announced that two babies in China were born with modified C chemokine receptor type 5 (CCR5) genes with the use of CRISPR-Cas9 gene editing [8]. He proceeded to explain that the edit was made to render the twins immune to human immunodeficiency virus (HIV) infection. 

There are numerous issues with the doctor’s actions which have led to the scientific community condemning his work, a prison sentence of three years for “illegal medical practice”, a court fine of 3 million yuan, and the termination of his position as a professor in the Southern University of Science and Technology [9]. So, what exactly went wrong? First, he was unsuccessful in achieving his main goal. Not only are Lulu and Nana still susceptible to HIV, they currently have versions of the CCR5 gene that have not existed in any other human genome throughout history [10]. These gene mutations are heritable, meaning they could be passed onto future generations  and we have no knowledge of what ramifications the mutations can have on the human body [10]. Dr. He and his team were also in gross violation of numerous ethical and scientific regulations. They neglected to follow necessary safety testing, refused standard procedure for the recruitment of participants, insufficiently informed the parents of the scientific procedures being performed, forged ethics documents, and evaded Chinese laws which ban the use of assisted reproductive technologies in those with HIV [11]. 

Dr. Jiankui He piloted work on gene editing and designer babies in a way that had never been seen before, with the implications of his actions still largely being a mystery. The idea that we can simply remove the genes responsible for some of the worst diseases in the world prior to birth initially seems like a utopian fantasy. However, most scientists agree that human germline genome editing is a very bad idea currently due to the ethical ramifications of such an endeavor [6]. 

Many voice their support for CRISPR being used to treat the nearly 10,000 monogenic diseases which affect 75 million people each year [2], but this opens a Pandora’s box of other “corrections” we could be making. Is it okay to remove deafness and as a result, eliminate the rich and thriving deaf culture [2]? What about eliminating neurodivergence and as a consequence, inhibiting the neurodiversity movement? We also must consider the fact that once we open the door to genome editing, this gives rise to the possibility of it being used for non-therapeutic purposes. For instance, should it be alright to change a child’s hair colour, increase their muscle strength, or make them more intelligent [2]? If we do this, what happens to those who are not able to afford such procedures? Will it create a new type of classism that discriminates against those without these “ideal” attributes? Such editing might also affect oppressed groups by attempting to change things like sexuality or gender identity [2]. 

All these questions make it evident that CRISPR can quickly become very dangerous by perpetuating societal principles of supremacy instead of being purely applied for disease treatment. Thus, there are still many unanswered questions regarding the utilization of CRISPR and the repercussions on societal structure and values. As can be deduced by Dr. Jiankui’s story, it will also be a while before we understand how to use this technology in a safe manner. As a result, designer babies don’t seem like they will be a reality anytime soon. Nevertheless, they spark a very interesting discussion on the potential of scientific advancement and just how far we as a civilization will go to achieve a perfect human species. 

References  

1. Kofler N. Gene editing like Crispr is too important to be left to scientists alone. The Guardian [Internet]. 2019 Oct 22 [cited 2021 Oct 22]; Available from: https://www.theguardian.com/commentisfree/2019/oct/22/gene-editing-crispr-scientists
2. Pang RTK, Ho PC. Designer babies. Obstetrics, Gynaecology & Reproductive Medicine. 2016 Feb 1;26(2):59–60. 
3. Morrison M, de Saille S. CRISPR in context: towards a socially responsible debate on embryo editing. Palgrave Commun. 2019 Sep 24;5(1):1–9.
4. Rose BI, Brown S. Genetically Modified Babies and a First Application of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR-Cas9). Obstetrics & Gynecology. 2019 Jul;134(1):157–62.
5. Jinek M, Chylinski K, Fonfara I, Hauer M, Doudna JA, Charpentier E. A Programmable Dual-RNA–Guided DNA Endonuclease in Adaptive Bacterial Immunity. Science. 2012 Aug 17;337(6096):816–21.
6. Greely HT. Stanford’s Hank Greely on CRISPR People and Designer Babies [Internet]. Stanford Law School. 2021 [cited 2021 Oct 22]. Available from: https://law.stanford.edu/2021/04/21/stanfords-hank-greely-on-crispr-people-and-designer-babies/
7. Guy BJ. ‘Designer babies’ could be just two years away, expert claims [Internet]. CNN. 2019 [cited 2021 Oct 22]. Available from: https://www.cnn.com/2019/11/19/health/designer-baby-analysis-scli-intl-scn/index.html
8. Wang H, Yang H. Gene-edited babies: What went wrong and what could go wrong. PLoS
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10. Cyranoski D. What CRISPR-baby prison sentences mean for research. Nature. 2020 Jan 3;577(7789):154–5.
11. Gorvett Z. The genetic mistakes that could shape our species [Internet]. 2021 [cited 2021 Oct 29]. Available from: https://www.bbc.com/future/article/20210412-the-genetic-mistakes-that-could-shape-our-species
12. Cyranoski D. The CRISPR-baby scandal: what’s next for human gene-editing. Nature. 2019 Feb 26;566(7745):440–2.