In Kazuo Ishiguro's novel, Klara and the Sun, the “lifted” are children who have undergone a genetic enhancement procedure designed to increase intelligence and academic ability. It’s something wealthier families choose for their children to secure better futures — elite education, careers, and status. Most top universities in the novel’s world primarily accept lifted students, creating a strong incentive to undergo the process. The parents take this risk in spite of the possibility of the procedure causing illness or even death. Such a dystopian world may not be as far in the future as you might think.
Genetic engineering has been practiced for five decades. It is the process of altering an organism's genome to change its characteristics in a particular way. It has been used to make food more nutritious, create synthetic insulin and provide promising treatments for illnesses including leukemia and sickle cell disease. Modern gene therapy is being used to treat eye diseases which can cause blindness, promote the growth of healthy skin or add supplementary copies of working genes that fix rare blood or immune system disorders.
Enter CRISPR. Remember the name. I am sure you are dying to know what it stands for so here it is: Clustered Regularly Interspaced Short Palindromic Repeats. CRISPR makes editing genomes much more precise, cheap, and easy than was possible earlier. The technique is considered so significant that the discoverers, Jennifer Doudna and Emmanuelle Charpentier, won the Nobel Prize in Chemistry in 2020, less than a decade after the discovery, something that rarely happens. Biologists began speaking about their life before and after CRISPR.
CRISPR is sold on the internet in kits, and is actively being used to do trivial things, such as to create fluorescent beer. Its ease of use has also raised concerns about “biohackers” who view gene modification as a right and alter microbes and organisms. “Mail-Order Crispr Kits Allow Absolutely Anyone to Hack DNA,” declared the headline of a November 2017 article in Scientific American. The iconoclast scientist Josiah Zayner has used CRISPR to hack into his own genes. (There is a docuseries on Netflix called "Unnatural Selection" where you can see it.)
There are even CRISPR jokes: Why has KFC asked scientists to edit the chicken genome? Because they want something CRISPR. And who is CRISPR's favorite actor? Gene Hackman
So what is the fuss all about? For that, first a little bit of biology. The body contains two types of cells: somatic and germ line cells. Somatic cells refer to any cell of a living organism other than the reproductive cells. The reproductive cells - the egg and the sperm - are called the germ line cells. A germ line cell passes on to the next generation while somatic cells don’t.
CRISPR is so precise that gene therapy in people with devastating illnesses seems feasible. For example, physicians could directly correct a faulty gene, say, in the blood cells of a patient with sickle-cell anemia. But that kind of gene therapy wouldn’t affect germ cells, and the changes in the DNA wouldn’t get passed to future generations.
In contrast, the genetic changes created by germ-line engineering would be passed on, and that’s what has made the idea seem so objectionable. “Germ line” is biologists’ jargon for the egg and sperm, which combine to form an embryo. By editing the DNA of these cells, it could be possible to correct disease genes and pass those genetic fixes on to future generations. Such a technology could be used to rid families of scourges like cystic fibrosis.
Germline genome editing leads to many bioethical issues. For example, what to do if the editing leads to occurrence of undesirable changes in the genome? Can parents give informed consent for editing the genomes of unborn children? If not, from whom do you obtain the consent? The counterargument is that parents already make many decisions that affect their future children, including similarly complicated decisions with IVF. Another fear is that germ-line engineering is a path toward a dystopia of superpeople and designer babies for those who can afford it. Want a child with blue eyes and blond hair? Why not design a highly intelligent group of people who could be tomorrow’s leaders and scientists?
Others believe the idea is dubious because it’s not medically necessary. It’s already possible to test the DNA of IVF embryos and pick healthy ones, a process that adds about $4,000 to the cost of a fertility procedure. A man with Huntington’s, for instance, could have his sperm used to fertilize a dozen of his partner’s eggs. Half those embryos would not have the Huntington’s gene, and those could be used to begin a pregnancy.
George Church, a geneticist at Harvard, likes to show a slide on which he lists naturally occurring variants of around 10 genes that, when people are born with them, confer extraordinary qualities or resistance to disease. One makes your bones so hard they’ll break a surgical drill. Another drastically cuts the risk of heart attacks. Church proceeded to tell the audience that he thought changing genes “is going to get to the point where it’s like you are doing the equivalent of cosmetic surgery.”
Regulations about gremline editing are variable and often lack teeth. For example, in many countries like Canada, France, Germany, Brazil, and Australia, clinical interventions in the human germline are expressly prohibited, with criminal sanctions that range from fines to lengthy prison terms. In other countries, such as China, India, and Japan, these interventions are forbidden, but with guidelines that are less enforceable. In the United States, there are no outright bans but any clinical trials would need to receive regulatory approval by the Food and Drug Administration.
There’s a risk that overly restrictive policies in some countries will encourage what might be called CRISPR tourism in others. Patients with means could travel overseas to jurisdictions where regulations are more forgiving or absent altogether. Excessive restrictions on research might lead scientists to continue their experiments behind closed doors. Trying to find a balance between maintaining regulatory environments that permit research and clinical applications but strict enough to prevent the worst excesses would be tough.
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