Thoughts on Gene Editing From the Science Community

Robert Pratta / Reuters
Editor’s Note: This article previously appeared in a different format as part of The Atlantic’s Notes section, retired in 2021.

Our next group of correspondents stood out due to their vocations: In one way or another, their chosen careers  brought them into the subculture of scientific thinking. These readers tended to be more favorably disposed to gene editing than others.

Take this reader, a “semi-retired school psychologist and a lover of science” whose daughter plans to become a clinical geneticist:

I agree with the premise of your article [that prophylactic gene editing could soon be mandatory] and am not frightened by it at all. Scientific advances have not, cannot, and should not be stopped. Since the first civilizations science has been dragging religion and society reluctantly along into a more technologically advanced future. What we gain from this seems always to be more than what we have lost.

A medical student who hopes one day to do gene editing was likewise eager for a future where it is used to cure disease––and even to direct the way that humans evolve:

Modern medicine, in its current form, is basically the answer to the question: “What is the best way to treat diseases whose cures cannot and will not ever be found?” Treating someone with cystic fibrosis, for instance, is an admirable thing to do, but it’s also an exercise in futility: That patient will undoubtedly die prematurely. Anything besides excising the mutant gene and replacing it with a normal copy is treading water and delaying the inevitable (though, obviously, the patients must still be treated).

In modern societies, infectious diseases and trauma are more or less under control (relative to developing countries and bygone eras). Curing genetic diseases (cancer loosely being included in this category) are currently a dead end. So, logically, addressing this head-on is the only next step.

I view gene therapy and editing as the way of the future, not only of medicine but also of humanity in general. It will start as the means for cures of currently incurable diseases. Eventually, it will be a means by which we can continue to evolve ourselves as a species. If 3.5 billion years of evolution churned our species out through the natural selection of random mutations, how much better can we do with logic and molecular precision? In my opinion, anything that can widely (and, potentially, permanently) change mankind and society for the better should be done.

I wish I shared the correspondent’s confidence that logic and molecular precision will serve humanity better in this realm than the decentralized systems of dating and mating have done so far. Reflecting on the decisions that literally every bygone generation might have made if able to edit genes, I fear that our choices will prove as imprudent in hindsight––and that’s not even accounting for unintended consequences.

The next reader is working to earn his Master’s degree in Biochemistry:

It is not unreasonable to imagine that in the near future gene editing will be a safe and effective means of preventing genetic diseases. It is also not unreasonable to imagine that in the case of many diseases, such as sickle-cell anemia or cystic fibrosis, which are caused by small mutations in a single gene coding for a functionally important protein, gene editing would be likely to prevent the disease without affecting the child in any other way. For these diseases, once it is demonstrated that gene editing works the way that it is supposed to, I think parents should be punished for failing to employ gene editing. I think that if it had been demonstrated that gene editing was safe, effective, and selective, refusal to use this technique to prevent disease would essentially amount to fear and mistrust of the scientific and medical communities. I really don’t think that’s a valid reason to allow another person to be afflicted by a preventable disease.

However, I draw a distinction here between expecting parents to make edits that will definitely prevent a debilitating disease, and expecting edits that reduce the risk of a disease that the child may or may not have ended up getting. I certainly wouldn’t be opposed to parents editing genes to reduce the chance of cancer, but I wouldn’t really expect it. There are a number of behaviors that we know reduce cancer risk which we don’t really expect parents to push on their kids. For example, parents could probably reduce cancer risk in their children by some small fraction by giving them grape juice every day or something like that. I don’t really expect parents to do that. If you can’t blame parents for not giving their kids grape juice you really can’t blame them for not editing the kid’s genome.

At the same time, he adds, “we can really only justify using gene editing for medical purposes”:

We are a long way from understanding our biology well enough to be able to make genome modifications to enhance intelligence or beauty or athleticism without risking horrible unforeseen side effects. But even if we did have the ability to do that, I still don’t think it would be justified because I don’t think we can tie these traits to an increased sense of happiness or fulfillment.

I am short and scrawny, and I’m perfectly happy with that. I know plenty of people who are perfectly content with being as dumb as rocks. I know plenty of smart people who are miserable. So, I’ll grant that I am basing my opinion here on a biased personal experience, but I really don’t think that we can say that it really is in the best interests of the child to alter superficial traits.

When discussing a child’s future, people often talk as if the parent’s preference is the most important thing. But parents don’t own their children. Parents are stewards of their children. I think that making “designer babies” would be an example of parents making self-serving decisions, rather than making decisions in the best interests of the child. I don’t think that is justifiable.

The next correspondent is a biochemistry grad student who works in a research group that specializes in genome-editing technology, and cautions against its near-term limits:

If gene therapy with Cas9 were at some future time as cheap, easy, and safe as an antibiotic treatment, then yes, I would support punishments for parents who forewent a cure for their children. In some cases, a genetic disorder is very similar to other macro-level disorders, e.g. genes can be broken in the same sense that a wrist is broken. While wrists can come in many healthy shapes and sizes and colors, “broken in two” is not one of them; likewise, while genetic diversity is important and natural and can’t always be cleanly mapped to disease, some genetic mutations are incontrovertibly damaging and lead to illness and suffering. Refusing a simple medical treatment for a disorder with a clear singular genetic root cause (of which there are fewer than one might think) would be as unethical as refusing to set a broken wrist.

But I don’t think gene therapy will be as cheap, easy, or safe as antibiotics in our lifetime—rather, my opinion is that gene therapy will be expensive, invasive, and risky (at least relative to an antibiotic pill) for the foreseeable future. I don’t expect gene therapy to become routine in the same way that oral therapies are, and so choosing not to subject your child to gene editing cannot be chalked up to negligence. (A contemporary example: Sovaldi is a drug that essentially cures Hepatitis C, but it costs $200,000 and there are other treatments—could you imagine a parent being prosecuted for refusing to pay for Sovaldi?)

Why am I so down on gene therapy?

First of all, regarding cost, the clamor surrounding the Cas9 patent dispute should give you an idea of how profitable the players in this field expect gene therapy to be. Gene therapy will always be more expensive than an oral antibiotic because the treatment requires many more steps (each of which is far costlier), is much lower throughput, and will require specialized care and oversight. For similar reasons, it will not be nearly as convenient for patients as filling a prescription. And as I’ve written elsewhere, our current early-generation gene-therapy tools and limited understanding of the link between genetics and disease means that gene therapy carries unprecedented safety risks. (For example, no currently approved therapy could cause permanent heritable genetic changes.)

These risks shouldn’t disqualify gene therapy as a possible future treatment, but they could certainly give the most informed and adventurous patient pause. In short, I believe technical limitations and cost and safety concerns will delay the debate over mandatory gene editing for decades at least. More pressing to discuss are the multitude of other ways that gene editing and GMOs affect modern life and medicine.