Down the slippery slope: Five experts discuss the ethics of gene editing

Down the slippery slope: Five experts discuss the ethics of gene editing

Fascinating new article in the New York Times Magazine: From gene editing to A.I., how will technology transform humanity? The Times sat down with noted experts Siddhartha Mukherjee, George Church, Jennifer Egan, Catherine Mohr and Regina Barzilay.

From the piece:

MOHR: The temptation to engineer what you think of as the best combination, as we become more capable of doing it, I think it’s going to be irresistible for a lot of people. You’re investing so much of your life into this little being, and you’re going to love this child, and you want to give them every advantage in life. We are already screening for diseases to avoid passing on our “bad” genes, but this same technology will let us start screening for our “best” genes — the ones we really want to pass on. As screening becomes cheaper, easier and more reliable, and more people are using assisted-reproductive technologies, I see us, as a society, sliding down that slippery slope pretty far, one couple at a time, each trying to do what’s best for the child they are hoping to bring into the world.

SIDDHARTHA MUKHERJEE: It’s certainly a tempting path, toward a potentially terrifying slope. But that only works if you do in vitro fertilization and create a pool of testable embryos. Then you have to biopsy those embryos-in-dishes, sequence their genes, identify and interpret the gene variants that you want to select (Variant A and B and C and D) and implant the “desirable” ones.

GEORGE CHURCH: Or we may turn to gene editing. If, for example, you have a dominant-allele disorder, like Huntington’s disease or Marfan syndrome, and you want to have children, you could edit the sperm, change that allele so that all sperm are healthy and your offspring will be fine. All sperm come from spermatogonial stem cells in the man’s testes. You can use editing tools and work on stem cells in Petri dishes so that you’re removing the bad allele and replacing it with DNA that has been designed and synthesized on computer-controlled machines. And then you can implant a pure population in which you’ve checked that the edit is what you wanted it to be, with all cells with only the desired “on target” changes. This has been done in mice. It’s a great opportunity. It’s only one time, and they’re good for life. In principle.

JANNOT: And why is that not being done now?

CHURCH: Until recently, we didn’t have good methods for doing gene therapy that we could apply to editing stem cells, sperm cells.

JENNIFER EGAN: How hard is it to edit genes?

MUKHERJEE: Well, that’s one of the surprises, is how extraordinarily easy it is. There are still technical challenges, and some of them may be hard to surmount, but the protocol is quite simple. We recently edited a gene in human blood stem cells to enable therapy for some forms of leukemia. We’ve sequenced the genomes of the edited cells and have not found a single “off target” effect thus far, although we are still looking. For other genes, off-target effects have been reported, so it seems that it’s case dependent. But over all, the fidelity of the system seems quite remarkable. ...

It’s like taking a massive encyclopedia and saying: Go to Volume 7, Section 8, Page 240, Paragraph 5, and change the word “this” to the word “that.” I’m simplifying, of course. ...

Our capacity to become more comfortable with the consequences of gene editing will come from diseases where the stakes, as it were, are more simple and higher — especially with a disease like acute myeloid leukemia, where there’s an extremely high mortality rate — and then we’ll backtrack our way into reproductive technology.

Mukjerjee's "The Gene" was one of the foundational pieces of research for my thriller Biohack, and it's fascinating to see the conversation about the ethical implications of recent advances in reproductive technology (or "reprotech") — especially in light of this week's news about Gene-edited babies in China & our brave new world.

Leave a reply

Your email address will not be published. Required fields are marked *