Designer babies

How biotechnology is allowing us to manipulate the genes of unborn babies

Theme: Ethics and Controversy

Venaya Binwani

Over the last few decades, scientists have been trying to find ways to eliminate genetic disease from our population, using a specific kind of biotechnology known as CRISPR/Cas9. CRISPR stands for clustered regularly interspaced palindromic repeats, a protein with the potential to alter our genetic code and save babies from being born with life threatening genetic conditions.[1] Though the name may not mean much to you (I assure you I’m thoroughly confused as well), this technology has sparked debate all over the world, surrounding everything from bioethics to social inequality. Before I get into the ethical and technical issues surrounding CRISPR/Cas9, let’s look at some of the basics of the human genome. 

The human genome refers to our entire genetic code, referring to all the DNA in our body. Our DNA is like a set of instructions stored within our cells, that makes up our physical characteristics, personality traits and influences how our body functions. Our genome is made up of 23 pairs of chromosomes, and within these chromosomes are genes. These genes are made up of tiny building blocks called bases - a bit like lego pieces that make up a giant building. When the bases of our genetic code are altered, it can have huge impacts on our body - and this forms the basis of where issues in genetic editing begin. If our genes represent a recipe, messing up our genes is the biological equivalent of adding salt to your cake, instead of sugar.

CRISPR/Cas9 technology involves injecting a protein into the body that has been programmed to target a specific part of a person’s genes, fixing the mutation that causes the disease, or altering other bodily cells that could help fight the illness[2].

One of the biggest clinical trials involving CRISPR technology took place in Hangzhou, China, in the attempt to treat patients with esophageal cancer. Cancer cells are able to detect a protein in our immune cells called PD-1, and manipulate these cells to inhibit an immune response. To overcome this issue, scientists ingeniously edited the immune cells of their patients, so that they would no longer produce PD-1, and could effectively kill and destroy the cancer. By July of 2019, 86 patients were cured using this method.[2]

Another way that CRISPR is currently being used is in the treatment of a neurodegenerative condition called Huntington’s disease. Huntington’s disease is caused by a single genetic mutation which stimulates the production of a toxic protein called Huntingtin, that accumulates in the brain, causing these cells to die. Symptoms include problems with muscle contraction, movement and balance, which can develop into speech and cognitive problems at a more severe stage. Scientists have been able to develop a way to target these damaged genes using CRISPR technology, which can reduce the production of this toxic protein by about 70%.[2]

Whilst this technology has been phenomenal in treating these genetically linked diseases, researchers are aiming to extend the use of CRISPR to human embryos, to prevent these disease carrying genes from being passed on to a child in the first place. However, the issue with this is that CRISPR technology is not always 100% accurate, which is a huge risk when editing the human germline. In our bodies, we possess two categories of cells, ‘somatic’ and ‘germline’ [1] Our somatic cells are those that have a specific function such as a brain cell or immune cell as those mentioned above, and the genes in this cell die with the individual. On the other hand, the cells present in a human embryo are germline cells, and any changes made to those genes will be passed on to every subsequent generation. [1] The unintended and unknown consequences of editing a gene today, for the future of the germline, is one of the reasons why scientists are apprehensive to use this gene editing technology, amongst a variety of other issues involving the technology itself and the complexity of our human genome.

In CRISPR editing, there may be ‘off target’ effects that alter the DNA beyond what it was intended to. The wrong genes may be cut out, the DNA molecule may not heal correctly, or genes may be edited that have more than one function[3] -  for example, altering the gene to make us resistant to HIV, could increase our mortality to the West Nile Virus which is transmitted by mosquitoes and produces symptoms such as fever, headaches and a skin rash.[4] [15]

Due to the complexity of our genetic code, it’s evident that CRISPR technology is not ready to be used to edit the human germline just yet[1][3].  However, provided these medical risks are overcome, there are still a variety of social and ethical implications that are making me question how we are going to  safely incorporate CRISPR technology into the medical field. This is mainly due to the fact that gene editing is not limited to preventing disease, because our genes determine features like eye colour, height, and influence personality and intelligence too[5]. Researchers are worried that the introduction of CRISPR to prevent development of specific diseases, will lead to the exploitation of this technology for social purposes, which gives rise to a variety of ethical consequences.[6]

Firstly, people of certain religious backgrounds may have objections to the idea of gene editing entirely, as predetermining a human’s traits can be seen as attempting to play the role of God, perhaps ‘meddling’ with the life ‘destined’ for them[7]. Secondly, the ability to engineer the ‘perfect’ child, runs the risk of babies being designed to fit the Western standard of beauty, consequently leading to the issue of eugenics[8] . Eugenics involves “practices that improve the genetic quality of the human population”[9], often resulting in the marginalisation of “inferior groups”, and is a term used to describe Hitler’s motivations to ‘purify’ or ‘improve’ the Aryan race.[10] This issue is particularly being explored in the pursuit to prevent disabilities, where ethical debates question whether gene editing to prevent conditions such as spinal muscular atrophy and achondroplasia, devalue the lives of those already living with them. [13]

Another large issue that arises from this is social inequality. Not withstanding the discrimination that may arise if people are being engineered to fulfill a Western standard of beauty, CRISPR can further widen the gap between social classes.[7]  It is likely that the development of CRISPR treatments will only be affordable to the most wealthy demographics of the world population, even though those living in third world countries may need treatment more urgently. For example, scientists have allegedly been able to alter the gene that makes us susceptible to HIV[4], and this disease is most prevalent in areas of Subsaharan Africa.

Apart from these ethical issues that remain, scientists are already using different forms of technology to prevent children from being born with genetic disorders. Couples who choose to seek out IVF treatment, can have their embryos screened in a process called ‘preimplantation genetic diagnosis’ (PGD) to check for over 400 hereditary conditions.[13]Future mothers in some countries can also use a new form of genetic testing called non invasive prenatal testing (NIPT) which takes DNA samples from the mother’s placenta, and tests for chromosomal defects such as Down Syndrome, Edwards and Patau, giving parents the option to abort their baby if there is a high risk of them having one of these conditions. To put it into perspective, women carrying fetuses positive for Edwards have an elevated risk of miscarraige, and babies born often don’t make it past their first month of life. 

These genetic tests are heavily regulated in the UK by the Human Fertilisation and Embryology Association (HFEA), and clinics require a license to carry out these genetic tests. For this reason, and the general evidence that parents value the health of their baby over their eye colour or height, the HFEA believes that genetic screening for non-medical traits will not be in demand any time soon.[13][11] A similar circumstance applies to Malaysia whereby PGD is only permitted for life threatening medical conditions.[14]

If this is the case, is germline editing even necessary?

Dr Helen O’Neill, a researcher in the Women’s Health department at UCL, suggests yes it is necessary, as continuing research into CRISPR/Cas9 on germline cells, is the way forward in better understanding the human genome. Should these massive leaps in biotechnology be implemented into everyday medical practice, it is important to consider how legislations and societal views will play a role in determining where we draw the line. With the genetic screening already used today, it is arguable that we have already taken steps towards designer babies. The question that still stands is: how much further are we willing to go?

Glossary:

1. Genome: The genetic material of an organism that consists of DNA

2. Bases: Building blocks of the genes

3. Mutation: A random change in the base sequence of DNA

4. Neurodegenerative: Conditions that arise from the death of neurons 

5. Germline: Series of cells that descend from earlier generations

6. Somatic: Specialised cells that have a particular role or function - DNA from these cells is not passed on

7. Eugenics: Practices that aim to improve the genetic quality of a human population

8. Downs syndrome: a genetic condition where the individual has one extra chromosome

9. Edwards syndrome: a genetic condition where the individual has an extra copy of chromosome 18 - many of these children die in the womb or within the first month of being born

10. Patau Syndrome: a genetic condition where the individual has an extra copy of chromosome 13 - 90% of individuals die within the first year of life

11. Spinal muscular atrophy: a genetic disorder causing muscles to waste away and the loss of motor neurons needed for movement. Number one cause of death in infants related to a genetic disorder.

12. Achondroplasia: a genetic disorder that results in shortened arms and legs - a form of short-limbed dwarfism

References

1. Vyas, K., Lang, F., Lang, F., Young, C. and Bergan, B. 2019,. Designer Babies: The Controversial Use Of CRISPR And Its Ethical Challenges. [online] Interestingengineering.com. Available at: <https://interestingengineering.com/designer-babies-gene-editing-and-the-controversial-use-of-crispr > [Accessed 25 April 2020].2

2. Fernández, C., 2019. 7 Diseases CRISPR Technology Could Cure. [online] Labiotech.eu. Available at: < https://www.labiotech.eu/tops/crispr-technology-cure-disease/ > [Accessed 25 April 2020].

3. Ledford,C., Nature.com. 2020. CRISPR Babies: When Will The World Be Ready?. [online] Available at: < https://www.nature.com/articles/d41586-019-01906-z > [Accessed 25 April 2020].

4. Lewis, T. 2015 There Are Really Good Reasons Why We Should — And Shouldn’T — Genetically Engineer Human Embryos. [online] Business Insider Malaysia. Available at: < https://www.businessinsider.my/arguments-for-and-against-editing-human-embryos-2015-12?r=US&IR=T > [Accessed 25 April 2020].

5. Lanese.N, 2019. 'Designer Baby' Technology To Make Smarter, Taller Kids Doesn’T Work Yet. [online] livescience.com. Available at: < https://www.livescience.com/designer-babies-far-from-reality.html > [Accessed 25 April 2020]. 

6. Anonymous. Yourgenome.org. 2015. Is Germline Gene Therapy Ethical?. [online] Available at: < https://www.yourgenome.org/debates/is-germline-gene-therapy-ethical#q0 > [Accessed 25 April 2020].

7. Anonymous 2019. 26 Designer Babies Pros And Cons. [online] ConnectUS. Available at: < https://connectusfund.org/26-designer-babies-pros-and-cons > [Accessed 25 April 2020]. 

8. Meyerson, C., 2018. Crispr Babies, IVF, And The Ethics Of Genetic Class Warfare. [online] Wired. Available at: < https://www.wired.com/story/crispr-babies-ivf-and-the-ethics-of-genetic-class-warfare/ > [Accessed 25 April 2020].

9. En.wikipedia.org. 2020. Eugenics. [online] Available at: < https://en.wikipedia.org/wiki/Eugenics > [Accessed 26 April 2020].

10. Lewis, T. Business Insider. 2015. The Major Concern About A Powerful New Gene-Editing Technique That Most People Don't Want To Talk About. [online] Available at: < https://www.businessinsider.com/gene-editing-history-of-eugenics-2015-12?IR=T > [Accessed 26 April 2020].

11. Hfea.gov.uk. n.d. Preimplantation Genetic Diagnosis (PGD) | Human Fertilisation And Embryology Authority. [online] Available at: < https://www.hfea.gov.uk/treatments/embryo-testing-and-treatments-for-disease/pre-implantation-genetic-diagnosis-pgd /> [Accessed 28 April 2020].

12. nhs.uk. 2017. Edwards' Syndrome (Trisomy 18) - NHS. [online] Available at: < https://www.nhs.uk/conditions/edwards-syndrome /> [Accessed 29 April 2020].

13. University College London,2020. Making Babies in the 21st Century [MOOC] Retrieved from https://www.futurelearn.com/courses/making-babies

14. RAHMAN, Z., 2006. Law To Ban Designer Babies. [online] The Star Online. Available at: < https://www.thestar.com.my/news/nation/2006/06/27/law-to-ban-designer-babies > [Accessed 29 April 2020]. 

15. Medlineplus.gov. 2018. West Nile Virus | WNV | Medlineplus. [online] Available at: < https://medlineplus.gov/westnilevirus.html > [Accessed 29 April 2020].