The Code Breaker: Jennifer Doudna, Gene Editing, and the Future of the Human Race

Nonfiction | Biography | Adult | Published in 2021

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Chapters 40-43Chapter Summaries & Analyses

Chapter 40 Summary: “The Red Lines”

In the wake of the 2020 coronavirus pandemic, scientists have become more open to different uses of germline editing, such as editing human genes to make people more resistant to viruses. Yet the question of whether germline editing is ethical remains one of the most profound questions humanity has ever faced.

While germline editing remains a provocative topic, somatic-cell editing has been widely accepted by the scientific community. In germline editing, edits are made in germ cells, such as sperms, eggs, and early-stage embryos, which means these edits are inheritable and affect every cell in the body. Somatic-cell edits involve living cells in certain parts of the body instead of reproductive cells. Such edits are not inheritable, so even if something goes wrong in the editing process, it will affect only the individual and not future generations. Despite the discomfort with germline editing, a kind of embryo editing is already being practiced in the form of pre-implantation diagnosis. If IVF embryos can be screened for certain genetic abnormalities, isn’t germline editing the next step? While some ethicists argue that the lines are blurred, Isaacson posits the germline is indeed a real line, and crossing it should tilt in the favor of treatment rather than enhancement.

Chapter 41 Summary: “Thought Experiments”

Before pronouncing that all germline editing is bad, one should consider its application in a few diseases, starting with Huntington’s disease. Caused by an abnormal repetition of letters in a DNA sequence, Huntington’s causes brain cells to die. It usually emerges in middle age, and patients slowly begin losing cognition and muscle control. Death is drawn-out and painful. Worse, since Huntington’s appears after a person’s childbearing years, they have usually passed the gene on to their children, who have a 50% chance of getting the disease. However, fixing Huntington’s should be relatively easy; the redundant letter sequence can be snipped without affecting much else. Germline editing could eliminate this terrible condition in human genes. Other alternatives, such as pre-diagnostic implantation, require producing a lot of viable eggs during IVF, which is not always easy. Adoption is not easy in every case; besides, there is the undeniable evolutionary impulse to reproduce.

While treating Huntington’s is a no-brainer, a disease like sickle-cell anemia presents a different challenge. As it turns out, people who get a copy of the sickle-cell gene from only one parent do not develop the disease but do develop immunity against malaria. Since most of the world’s sickle-cell sufferers live in sub-Saharan Africa, where malaria is endemic, editing the sickle-cell gene out of their germline creates a Catch-22 situation.

There are other ethical considerations too. Suffering builds empathy and character. Franklin Roosevelt was forged by polio. Should the possibility of future Roosevelts preclude the need for the polio vaccine?

The most frightening frontier of germline editing remains the enhancement of intelligence. Improving cognitive skills like memory and focus would be useful for humanity. However, improving wisdom remains a more elusive concept. Without wisdom—which is difficult to quantify or map—enhancing ingenuity and smarts can be dangerous.

Chapter 42 Summary: “Who Should Decide?”

In October 2019, the National Academy of Sciences posted a video on twitter to spur a broad public debate about gene editing. However, the video’s tone was misguided; it featured everyday people stating which body parts or functions they wished gene editing would improve in them and their offspring. While someone wished gene editing could take away their dyslexia, another wished to be taller. Bioethicists immediately protested the video on Twitter, with many users claiming the subject matter was suspiciously close to the 1930s Nazi agenda for genetic superiority. The video was soon taken off the web.

The fiasco around the video raised the question: Would should decide if gene editing is beneficial? There are two perspectives to any moral issue, one favoring the individual and the free market, and the other favoring the greater societal good. So, which camp has the more superior view? The question is open-ended, but one reason to restrict germline editing in the free market is that it could propel inequality into a “new disconnected orbit.” In short, rich, privileged people would buy better genes, turning the world’s financial inequality into frightening genetic inequality.

Finally, there is the question of playing god and interfering with evolution. Myth and fiction have always warned of the unintended consequences of trying to upstage nature, but it can be argued that since human beings are part of nature, their inventions are also natural. The most profound argument against eliminating human flaws was articulated by Harvard philosopher Michael Sandel: If human beings take perfection for granted, empathy for those less fortunate would certainly diminish. Therefore, wisdom suggests that germline editing should proceed, but with checks and balances aplenty.

Chapter 43 Summary: “Doudna’s Ethical Journey”

Doudna’s position on using CRISPR-Cas9 as a gene-editing tool in germ cells has evolved over time. An issue raised at the 2015 Napa conference stuck with her: Not using gene editing to alleviate suffering could also be unethical. The testimonies of patients and families made her return to that viewpoint. Once one has seen the face of someone suffering from a condition like Huntington’s, it is difficult to argue against germline editing. Doudna’s thinking was also informed by conversations with Janet Rossant, the head of research at the Hospital for Sick Children in Toronto, and George Daley, the dean of Harvard Medical School.

Yet Doudna was also concerned about the inequality that removing all restrictions on germline editing would herald. So, her take on the subject boils down to what is medically necessary. If germline edits are used to restore a mutated gene to normal when medically necessary, as in the case of certain disorders and diseases, then they are fair. However, germline edits that are medically unnecessary—as in the case of Jiankui’s work on the CCR5 gene—or that simply enhance a trait—like IQ or height—are socially and morally questionable.

Chapters 40-43 Analysis

In Chapters 40-43 Isaacson does a deep dive into the ethics of gene editing. To examine the issue holistically, he conducts “thought experiments” using real and hypothetical cases of diseases. Though the case for treating Huntington’s disease with gene editing is straightforward, the case for sickle-cell anemia is more complex. However, the actual experience of a sickle-cell patient, like David Sanchez of California, can add even more complexity to the issue. Sanchez, a high schooler who loves basketball, suffers from pain so debilitating he often has to double over. He needs monthly blood transfusions from a healthy donor for temporary relief. Yet when asked if he would want sickle cell to be edited out of his germ cells, his reaction was mixed. He reflected, “I don’t think I would be me if I didn’t have sickle cell” (337). Sanchez says that the choice to edit sickle-cell anemia should be left to the patient and not the parent.

Sanchez’s perspective raises extremely pertinent questions about bodily autonomy and suffering as choice. For instance, bioethicist Rosemarie Garland-Thomson, born with distorted arms, wrote that her genetic condition gave her a “head-start […] for human flourishing” (338). Would it be fair to edit her genome for “normal” arms? Who defines what is normal?

Not every sickle-cell sufferer shares Sanchez’s view; not even Sanchez expresses the same view over time. When Sanchez was later asked if he would want his future children to undergo gene editing for sickle cell, he said yes. Given such shifting and evolving information, how can society reach a consensus on modalities for gene editing? The text suggests that a consensus does not need to be a monolith; it needs to constantly evolve, just like the issue of gene editing. Most importantly, questions around gene editing should keep being raised because questions lead to answers. Isaacson raises a few more: As humans become the only species to edit their genetic makeup, will the rich have the power to buy the best genes? Will societal standards of perfection impact parents’ choices about the “right” genes? Or is asking such questions being overdramatic?

Such questions can also be applied to issues of height, deafness, muscle-building and sports, superhuman enhancement, and mental health. When it comes to mental health, the suffering from schizophrenia, bipolar disorder, and other mood disorders can be terrible. Yet many creative visionaries, from Van Gogh to Sylvia Plath, had mental health issues. If parents were to edit the gene for, say, bipolar disorder, would they also be affecting their child’s creativity? In such cases, would a parent rather their child be creative or happy?

In Chapter 42, Isaacson explores if the common good should be the standard for permissible gene editing. For instance, removing the gene for Huntington’s would be a benign choice for society, but editing the gene for height would be an unnecessary and possibly disruptive choice. The problem with this approach is that zones of individual and common good can sometime infringe upon each other. Moreover, those who support a libertarian ideology would say that individual will trumps other considerations. For instance, an individualist would argue that wearing a mask during a pandemic is a choice, while someone arguing for the community would say masks are mandatory. These contrasting perspectives define the political divide of contemporary society between those who advocate for absolute personal liberty, the free market, and privatization, and those who promote the good of the community and have a more socialist and environmentalist outlook. Given such radically different views, it would be difficult to use the public-good yardstick to modulate gene editing.