Abstract: This paper explores the use of Preimplantation Genetic Diagnosis (PGD) and in Vitro Fertilisation (IVF) to prevent the inheritance of Huntington's disease which is a fatal neurodegenerative disorder.  I surveyed people with first hand experience with HD on how they perceive the ethical and emotional aspects of using PGD to prevent Huntington's Most participants supported PGD as a way to prevent huntingtons but also showed concerns about cost and accessibility. Some were hesitant to have children all together, not wanting to be a financial burden on their children or forcing them into a caretaker role. The results suggest a need for greater accessibility and education on reproductive technologies particularly due to the fact that they are becoming more relevant for the future.

 

What is Huntington's disease?

 

Huntington’s disease affects approximately 5 per 100,000 people in Western countries, with thousands more at risk due to family history and close relatives with HD. In the United States alone, an estimated 30,000 people live with Huntington’s, while more than 200,000 are genetically at risk [1]. The absence of any cure or gene-modifying treatment makes the need for reproductive options like PGD even more urgent. Without intervention, HD remains a genetic coin toss repeated every generation. Huntington's disease (HD) is a rare autosomal dominant neurodegenerative disorder caused by a gene mutation in the HTT gene on chromosome 4. The mutation is an abnormal CAG repeat expansion, more than 36, that leads to the creation of a misfolded huntingtin protein [2]. These misfolded proteins clump together in neurons, most notably in the striatum and cortex, and these areas of the brain govern movement and behavior. Constant neuron death leads to uncontrollable movement (chorea), mood changes, and a general cognitive decline, eventually leading to loss of independence and death [3]. The CAG repeat size is inversely related to age of onset. 

     In unaffected individuals, the huntingtin protein plays a vital role in brain development and neuron survival and supports synaptic communication and may also protect cells from programmed cell death. Although its exact functions are still being researched. It is clear that the protein is necessary for development as mice embryos without it do not survive[4]. 

     Since HD is a dominant autosomal disease, Huntington’s has a 50% chance of being passed on and CAG repeats can increase in future generations. This phenomenon is better known as genetic anticipation and explains why some children show symptoms earlier than their affected parents. If the male parent carries the gene, the CAG repeat can expand dramatically during spermatogenesis, which can lead to juvenile-onset HD in offspring [5]. 

     HD is caused by a CAG(cytosine-adenine-guanine) trinucleotide repeat expansion in the HTT gene located on the short arm of chromosome 4. In unaffected individuals the CAG sequence is typically repeated 10-35 times. Whereas 36-39 repeats is known as reduced penetrance which means symptoms might develop. More than 40 repeats means that symptoms will develop at a later age. whereas 60+ repeats mean juvenile HD [6]. These CAG repeats code for a polyglutamine (polyQ) tract in the huntingtin protein. Expanded polyQ tracts expose hydrophobic residues resulting in protein misfolding. This misfolded protein shows amyloid-like fibrils. These misfolded proteins lead to aggregation into intracellular inclusion primarily in neurons of the striatum and cerebral cortex. These aggregates disturb cellular function like transcription and mitochondrial integrity which introduces an energy deficit eventually leading to cell death and progressive neurodegeneration [2].

     The striatum which is part of the basal ganglia is notably vulnerable leading to the symptoms of HD, chorea, emotional distress and cognitive decline [7]. Importantly, the number of CAG repeats is inversely related to age of onset. Genetic anticipation in HD is tied to repeat instability in gametogenesis, where CAG repeats expand during gamete formation. Some gametes may have 41 repeats while some others may have 60+ repeats [4] and this is why PGD is so important . Due to the biological predictability of the disease, early and accurate genetic diagnosis can be used to prevent passing on the disease.

 

Reproductive technologies for HD

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     The disease is passed on because the disease slips through natural selection due to symptoms showing up after they have already had kids. And the mutation is sadly stable enough to be inherited. So families turn to reproductive technologies like PGD and IVF to prevent passing on the disease. PGD is paired with IVF to determine embryos that lack the HD mutation [8]. Eggs are extracted and fertilized in the lab. When the embryo is at the stage of the blastocyst, cells are extracted and tested for the CAG repeat number on the HTT gene. Mutation-free embryos are selected and implanted, reducing the risk of passing HD substantially [8]. While these technologies are full of promise, they also raise tough ethical issues. Choosing which embryos to implant raise questions about fairness, accessibility and the moral implication of selecting certain genes for the life of others. PGD is a life saving scientific breakthrough but it is also “playing god”, creating a slippery slope towards designer babies [9]. These ethical implications are especially relevant as reproductive values become more widely available. 

     Preimplantation genetic diagnosis is used with In vitro fertilization to eliminate the disease at its root by selecting embryos without the mutant allele, it can also be used to count chromosomes to detect down syndrome [10]. After the eggs and sperm are fertilized in a lab, the embryos are cultured until the blastocyst stage (≈5 days), at which 5-10 trophectoderm cells are harvested and biopsied; this minimises risk to the embryo's development . In the case of HD, the cells are tested using polymerase chain reactions. Polymerase chain reactions are used to amplify specific DNA sequences such as the HTT gene and count the number of CAG repeats. This process includes cycles of denaturation and annealing of primers.

PGD success is still not guaranteed. According to recent clinical data, live birth rates per embryo transfer range between 25–45% [11], depending on maternal age, embryo quality, and the specific lab. For families facing HD, this means multiple IVF-PGD cycles may be necessary. 

 

Ethical considerations

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     Either way, selecting embryos raises sensitive questions. Ethicists like Savulescu (2009) argued that whether selecting specific embryos is responsible parenting or unethical manipulation of life, Should having children ever be a “calculated” decision [12]? It's a well known fact that PGD and IVF are expensive and mostly available to the wealthy, so is PGD a truly ethical solution or just an elegant way of exclusion. PGD involves choosing embryos that also means discarding some, so does this mean that lives with HD are less valuable [13]? Some ethicists argue this creates a genetic underclass where some people are born with diseases society tried to prevent [14]. If we allow removing suffering, how long till we start editing out differences?  What about autism, IQ, deafness and more where is the line drawn and who gets to draw it?

     Disability rights advocates have raised concerns about PGD promoting a “search and destroy” mentality toward certain genetic conditions [15]. While preventing suffering is a noble goal, critics argue that widespread embryo selection may reinforce the idea that lives with genetic conditions are less valuable (Philosophers call this argument the expressivist objection.) [16]. For example, activists within the Deaf community have expressed that deafness is not a defect, but a cultural identity which raises ethical concerns about PGD being used for non-life-threatening traits [17]. 

     There is a fundamental difference between implying that a life with huntingtons is less valuable and choosing to prevent a child from an eventually fatal disease. The expressivist-objection blurs the line between these 2 things. A parent who chooses to use PGD is not suggesting that lives with huntingtons are less valuable. They are just choosing to prevent suffering. This distinction is supported by the survey findings themselves. The survey shows overwhelming support for the use of PGD. If this objection was justified, We would expect HD-affected individuals to oppose PGD

 

Methods 

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     A survey of 11 questions was created using google forms and distributed online on r/huntingtons which is a subreddit familiar with Huntingtons. Participation was voluntary and no information was collected. Respondents were given basic information on PGD and IVF to ensure basic understanding. Questions were a mix of multiple choice and long answer questions to identify statistical patterns and personal narratives 

However, this sample is limited to 40 individuals. Which may not be representative of the broader population affected by Huntington's disease, therefore findings should be interpreted as exploratory rather than definitive. A total of 40 individuals were surveyed. All of whom were directly affected by HD from a variety of backgrounds.

 

 

[See Figure 1 below]

Fig 1:the people that responded to the survey 50% of the respondents were tested positive for huntingtons

25% of the respondents were caregivers and/or family members of someone with HD 25% were at risk individuals

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     This targeted group offers a deeper insight and emotional authenticity that would not be possible in a  general population sample The survey included questions such as: “Would you consider using PGD if you were planning to have children” and “ How Do you feel about the ethical side of using PGD/IVF to avoid Huntington's?" Open-ended responses encouraged participants to explain their reasoning and share personal experiences. 

 

Results 

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     Survey responses revealed strong emotional themes and ethical reasoning behind participants’ views on PGD and HD. Respondents were also asked about emotional impacts of reproductive decision-making. Several wrote about experiencing guilt, grief, or fear of watching their children suffer as they had watched parents or siblings suffer. One HD-positive participant shared, “I tested positive, so why would I even want kids knowing that I won't live long enough to see them grow up” Another respondent said, “when it comes to using PGD its voluntary eugenics but I think this becomes a necessary evil to prevent this horrible, incurable disease” These insights reveal that for many, PGD is a trauma-informed choice more than a theoretical debate.

     The term “voluntary eugenics” raises doubts for the justification of PGD. However, what made historical eugenics different and wrong is that it was state coerced, targeted marginalised groups, and stripped reproductive autonomy based on social and ethnic prejudice . PGD does the opposite,  it is a private choice which expands reproductive autonomy and prevents suffering.

     Despite being exploratory and derived from a limited, self-selected sample, the findings provide an important perspective on what individuals impacted by Huntington’s disease think about the ethical and emotional dilemmas raised by reproductive technologies.Most people I surveyed were 29-40 years old with a mere 2 responses from people under 18 and 50% of the respondents were positive for Huntington's Participants were asked if they knew about PGD.

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Fig 2: shows the participants knowledge on PGD.

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Fig 3: shows the willingness to use PGD/IVF to have children

 

     As shown every participant knew about PGD. Participants were also asked if they would consider using PGD/IVF to have children. As shown 70% of the participants would use PGD/IVF while 2 individuals had children  using IVF and PGD. while 6 individuals said maybe and 2 said no. 

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Identifying cost as a major barrier.

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     When asked if insurance fully covered PGD/IVF would they be more likely to consider it?

92.5% said “yes definitely”

7.5% said “no, I wouldn't"

     While cost was identified as the largest barrier. Countries like the UK and Australia have begun reimbursing the use of PGD for families at risk of severe genetic disorders, recognizing it as a preventative healthcare measure. In contrast, nations like the U.S. or India leave this burden to the individual, limiting access to those with financial privilege. Insurance companies currently treat PGD as elective but for families carrying dominant mutations, it’s a lifesaving preventative intervention. Future policy reforms could include mandatory insurance coverage for PGD for hereditary diseases, closing the equity gap for those carrying these devastating mutations. Without legal and policy changes, PGD risks becoming a tool only available to the privileged few [18].

      When asked about potential barriers to accessing PGD and IVF, most respondents  did not mention accessibility issues; some briefly touched upon it Some participants did mention that PGD borders on eugenics but still supported using it for HD. Some said “it's totally unethical to not use PGD/IVF to avoid huntingtons since you are bringing someone into this world with a 50% chance of developing a fatal, incurable disease”. While a small percentage of people cited not wanting children at all not wanting to force their children into a caretaker role.

     The results of the survey showed how individuals affected by Huntington's make perceive PGD and IVF showing overwhelming support for PGD. but these results also highlighted complex personal decisions, emotional burdens and future responsibilities. These findings raise important questions on the ethics of genetic screening about fairness, accessibility and the long term effects.

     The results highlight the overwhelming amount of support for using reproductive technologies preimplantation genetic diagnosis (PGD) and in vitro fertilization(IVF) to avoid passing on HD, so clearly awareness is not an issue. Accessibility was not mentioned as a major issue by respondents but cost was presented as the most significant barrier which is consistent with the current capabilities and high financial burden of PGD and IVF treatments, especially when multiple cycles are needed. More so, respondents did not mention any ethical objections to using PGD to prevent HD. In HD communities there is a pragmatic view on using reproductive technology, driven by personal experiences and a desire to prevent suffering. There is a contrast present with societal ethical debates, where concerns such as designer babies and essentially voluntary eugenics are argued against embryo selection, however, it’s important to distinguish between selecting against a fatal, untreatable neurodegenerative disorder and selecting for traits like height or eye color. Most respondents drew this line indistinctively. For people affected by HD, the decision is not based on ethical dilemmas and more about responsibility and future decisions. Some respondents even said how it's totally unethical to not use PGD when it is available.

      A significant pattern that emerged from the survey is that many respondents chose not to have any children. Citing fear of forcing a caretaker role on them not wanting to be a burden on others or concern about the emotional toll of this disease, not being able to see their children grow up. Not wanting to subject their children to dealing with a parent in late stage HD. The psychological impact of being affected by HD severely influences reproductive decision making [19]. The desire to use any means to prevent HD may not be caused by wanting to “design” a child but prevent generation long suffering. This is a major distinction between enhancement and prevention . 

     In this particular survey, most participants did not cite religious or other objections to the use of PGD. Instead, the focus remained largely on practical concerns such as cost, success rates, and the desire to prevent future suffering. This suggests that for many families directly affected by HD, the priority may lie more in disease prevention than participating in philosophical or moral debates.

 

Further discussions

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      From an evolutionary standpoint, PGD might interfere with natural selection, but it could also be seen as an effort of human adaptation by using technology to prevent an incurable and inheritable disease. In cases of juvenile HD, where symptoms rise before reproduction, natural selection theoretically reduces transmission. However in the case of adult onset HD, the later expression of symptoms does not allow natural selection to take place and allows the gene to stay relevant and persist in the gene pool. Artificial reproductive technologies compensate for this evolutionary blind spot. Reproductive technologies represent compassionate selection, which prioritize health and well being to provide the best life they can for their offspring. 

     While it's worth noting that PGD is powerful, it is not accessible to everyone. The high cost and lack of coverage signify that reproductive tech is still unequally undistributed. This means that people with financial means can protect their offspring from HD while people who do not have the means face minimal options. Raising concerns about reproductive justice and whether future policy should provide support and for these technologies for individuals with heritable genetic diseases 

     The use of PGD to prevent Huntington's disease is ethically justified. HD is not    comparable to diseases that do not drastically decrease life expectancy. HD strips away independence and quality of life not only from those who inherit it but also from entire families affected by it who end up becoming long term caregivers. Why would anyone want their children to go through that suffering if there is technology that can prevent it. Having any means to prevent this disease should be celebrated. Huntington’s disease is not just a genetic disorder, the onset leads to an inevitable fatality. Nonetheless, this view is not universal, many believe that every life deserves a chance regardless of genetic condition. Many worry that PGD might create a stigma to those living with HD. These concerns are valid, as they highlight the use of science and balancing it with compassion. It is absolutely necessary that PGD does not lead to the devaluation of the lives of people living with HD. The goal of PGD is to reduce suffering without reducing humanity. 

Parfit's non identity problem poses a deeper challenge on the harm based justifications for the use of PGD. It states that a child born with HD is a distinct person from the one who would be born without it, so PGD cannot be justified on grounds of  benefiting the future child since the child with HD simply won't exist [20]. However, the justification for PGD should not rest on the future child at all. It rests on the reproductive autonomy  of the parents. It was never primarily about benefiting a future child, rather about preventing intergenerational suffering and reducing caregiver burden. 

 

Conclusion

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     Looking ahead, the rise of gene-editing tools like CRISPR-Cas9 and in vitro gametogenesis may one day offer more options for HD with recent trials showing promising results . However these technologies are still developing, often facing ethical and safety barriers. Until then, PGD remains the most realistic and one of the only ways to stop the transmission of HD at its genetic root. More education, outreach, and financial support are needed to make sure all families can make informed, empowered reproductive decisions.

Huntington’s disease forces families into heartbreaking decisions, and for many people, PGD represents more than a medical option. Through a combination of IVF and genetic screening, parents affected by HD now have a chance to end a painful legacy. This paper has explored the science, the lived experience, and the ethics surrounding this choice. From the unpredictable devastation of expanding CAG repeats to the emotional toll carried across generations, affected families make it clear that PGD is not about designing babies but to prevent suffering

     While these reproductive technologies offer hope, they also force us to ask difficult questions about accessibility and the ethics of reproductive choices. Should the ability to prevent a fatal inheritable disease only be limited to those who can afford it? Where do we draw the line between preventing suffering and exerting control over life itself? The people surveyed such as those living with HD or caring for someone who is, showed us that these questions aren't hypothetical. They are deeply personal, emotional, and often urgent.

     Yes, PGD raises tough ethical questions. However these questions must also be asked alongside the voices of the people who experience HD every day. In the end, the goal of PGD is not to create a perfect child but to offer a future free from unnecessary suffering. As science advances, our challenge is to make sure that compassion keeps pace with technology because while we may be able to alter genes in a dish the true measure of progress will be how we support the people who have to make these decisions and ensure that they are never left behind.