Chapter 1: Introduction to Designer Babies

In November of last year, Chinese researcher He Jiankui shocked the world by announcing the birth of genetically edited twin girls. This news sparked widespread outrage for several reasons.

Firstly, there is a broad consensus that the gene-editing technique he used, CRISPR-Cas9, remains too risky for human applications. Jiankui utilized CRISPR to eliminate the CCR5 gene from embryos, with the goal of making them resistant to HIV. It is worth noting that individuals without this gene have shown resistance to the virus. However, this practice—known as germline editing—involves altering the genetic makeup of embryos and carries significant risks, especially since the changes are heritable. Up until Jiankui's experiment, CRISPR had never been used to modify human embryos meant for implantation.

Moreover, Jiankui allegedly misled the parents involved in the trial by suggesting they were participating in an "HIV vaccine" study, thereby obscuring the true dangers associated with the research.

The father of the edited twins expressed concern about passing his HIV-positive status to his children, even though paternal transmission of the virus is exceedingly rare. This risk could have been mitigated through a simple procedure called sperm washing. Thus, the potential advantages of this germline editing application did not outweigh the significant known and unknown risks involved.

When Jiankui eventually presented his findings, those in attendance were reportedly horrified. His own results indicated that the embryos were mosaics, meaning the CCR5 gene had been successfully excised from only a subset of the cells. This outcome not only limits the efficacy of the intervention but also raises serious health concerns for the twins.

Despite the backlash against Jiankui's actions, the long-standing opposition to manipulating the human germline is beginning to wane. Influential organizations like the National Academies of Sciences in the US and the Nuffield Council on Bioethics in the UK have released reports suggesting that germline editing could be acceptable under certain conditions. A significant number of experts in the CRISPR debate argue for the development and approval of germline editing specifically to eliminate genes responsible for certain monogenic disorders such as cystic fibrosis, Tay Sachs, and Huntington's disease.

These disorders are particularly notable because they are linked to a single gene. In the case of dominant conditions like Huntington's disease, possessing just one copy of the gene guarantees that the related disease will occur. This clear relationship between genetics and disease is relatively uncommon, as most health conditions result from a complex interaction of multiple genetic and environmental factors. Additionally, monogenic disorders often have severe consequences and lack effective treatments.

Proponents of germline editing argue that once the technology is refined, it will be morally justifiable to use it for these conditions because: 1) it doesn't involve the ethical dilemmas associated with "designer babies"; 2) the clear genetic basis for these disorders minimizes the risk of unintended consequences; and 3) it could prevent significant suffering in individuals for whom there are no viable therapies.

However, it's crucial to clarify that germline editing should not be classified as a therapy or treatment. Therapeutic interventions aim to alleviate the suffering of individuals already afflicted by conditions. For instance, removing the cystic fibrosis gene from the lung cells of affected patients would be considered a treatment. In contrast, using CRISPR to modify embryos to create a person who might not otherwise exist represents a form of reproductive technology.

This distinction is important, as existing reproductive technologies can prevent the transmission of monogenic disorders in most cases—a fact often overlooked by advocates of germline editing. For example, Preimplantation Genetic Diagnosis (PGD) allows couples with genetic disorders to select healthy embryos created through in vitro fertilization. Given the rarity of genes causing most monogenic conditions, many couples can produce viable embryos without the disorder. PGD can help identify and implant only those embryos free from the genetic condition.

However, in the extremely rare situation where both parents carry two copies of a gene linked to a dominant monogenic disorder, all embryos produced will inherit that gene. Even in such cases, couples can still utilize donor sperm or eggs to conceive a healthy child related to one parent.

Proponents of germline editing often cite this rare scenario as a prime example of the technology's necessity. They argue that the limited need for such interventions dismisses concerns about its societal impact. Yet, this reasoning raises several issues.

First, it is essential to recognize that the small number of individuals who would benefit from germline editing could still opt for adoption. Therefore, pursuing germline editing for such a limited group of people raises the question of how crucial genetically related children truly are. While many people desire genetically related offspring, whether this preference should be upheld by science and law—despite longstanding ethical arguments against altering the human germline—is debatable. In a world with numerous unwanted children and pressing environmental concerns, perhaps the quest for genetically related children should be reconsidered.

Moreover, it should be noted that both parents in a couple unable to produce healthy embryos are likely to suffer from the genetic condition in question. The child born from germline editing could potentially lose one or both parents early in life—an ethically concerning scenario for obvious reasons.

Finally, while supporters use the limited necessity for germline editing to minimize ethical concerns, one might question why so many resources should be dedicated to developing a reproductive technology needed by so few. These limited cases, which evoke sympathy, may not be the ultimate goal but rather a gateway to broader applications of germline editing. For instance, advocates of drug policy reform have employed similar strategies to legalize cannabis, starting with limited medical applications and later pushing for full legalization as society becomes accustomed to the substance.

In the realm of germline editing, approval for preventing monogenic conditions could pave the way for extending the technology to eliminate genes linked to conditions arising from multiple genetic and environmental factors. The National Academy of Sciences has indicated that it may someday be acceptable to edit BRCA genes from embryos, although, unlike cystic fibrosis and Huntington's disease, possessing a BRCA1 gene does not guarantee breast cancer will develop. Thus, this application of germline editing could veer into enhancement territory by removing even the predisposition to disease.

Moreover, such uses of germline editing could be riskier due to our limited understanding of the complex interplay of genetic and environmental factors. For example, it remains uncertain how removing the BRCA1 gene might affect the expression of other related genes and overall health. The additional risks associated with such interventions may be difficult to justify, especially considering that breast cancer is now a relatively manageable condition.

Ultimately, it is plausible that some advocates of germline editing, despite public statements to the contrary, are enticed by the idea of "designer babies." This desire is already evident in our society, with numerous IVF clinics in the US offering PGD for non-health-related traits like eye and skin color. Studies also suggest that eliminating the CCR5 gene could enhance cognitive abilities. A recent article raises the possibility that Jiankui’s choice to remove the CCR5 gene may have been driven by its enhancement potential rather than solely protecting against HIV. A researcher investigating the cognitive effects of CCR5 removal from mice noted interactions with individuals in Silicon Valley who exhibit a concerning interest in designer babies with superior cognitive functions. Therefore, even if germline editing is initially sanctioned only for a limited set of therapeutic applications, advocates may eventually push for uses that revive all the ethical and safety concerns associated with designer babies.

In conclusion, many proponents of germline editing appear to be less than transparent about their motivations for supporting this technology. Given the profound implications for individuals, society, and humanity's evolutionary trajectory associated with exerting unprecedented control over human genetics, it is crucial that discussions surrounding germline editing are open and candid. Only then can the public and governments effectively oversee the responsible advancement of this technology.

Chapter 2: Ethical Considerations and Future Implications

This video, titled "The Ethical Dilemma of Designer Babies," delves into the moral concerns surrounding the practice of germline editing. It highlights the complexities and potential consequences of creating genetically modified humans.

In this video, "Should We Make Designer Babies?", experts discuss the implications of designer babies and the ethical questions that arise from manipulating human genetics.