Posted on November 29, 2018 at 10:43 PM
By Jon Holmlund
Much has already been written and said—mostly in condemnation–about this week’s announcement of the birth of the first gene-edited baby (or, better, babies—there are twins). A gene was altered in embryos created through in vitro fertilization, and then the embryos were transferred to their mother, who carried them to term and, reportedly, normal delivery. The babies are said to be in good health.
A couple of good summary articles, written for non-specialists, are online from Science News and the science journal Nature. Follow those links to read more than your correspondent can write here in a short blog post.
The scientist who did this used the CRISPR-Cas9 system to alter a gene called CCR5, which is a receptor, or docking post, for the HIV virus. Presumably, altering CCR5 would reduce the risk of HIV infection if not prevent it altogether. The twins’ mother is reportedly not infected with HIV, but the father is. How much risk this placed the babies at is questionable—usually, babies infected with HIV become infected because of transmission from an infected mother. HIV can cause infection through other receptors, and altered or disabled CCR5 can increase risk of other infections. So, overall, the medical need was questionable, there were (actually, are, one needs to see how their health is in the future) potential correlative risks to the babies, and there were likely other means to avoid what appears to have been an unlikely prospect of these babies getting HIV from their father. Because of concerns like this, ethicists have been arguing that the action violates human research ethics, in which risks to subjects must be minimized, and benefits must outweigh risk. Any ethics board reviewing a proposal would assess this rigorously, and ask whether there are safer alternatives to the research.
The experiment is said to have worked in this sense—analysis of their DNA shows that the target gene, and no other genes, was altered as intended. Clearly, the rationale for the editing was to show that it could be done. George Church, ever the risktaker in the name of “advancing the field,” argued in an interview that because HIV is incurable and there is no vaccine for it, that constituted an unmet medical need in this case. He also argued that the scientist in question only failed to complete the proper “paperwork,” and that there might be long-term safety issues with heritable gene editing but that would not be dispositive because he is quite confident that those risks will be small, like the risks of diagnostic medical imaging. To all of which we must respond, “rubbish.” We do not know what the long-term risks are, ethics boards are rigorous about risk assessment for any and all experimental procedures, and the medical need in this specific case was dubious.
Nature reports that this work “has prompted an outcry from scientists, who are concerned that [the scientist] leap-frogged international discussions on the ethics of such interventions and has put the children at risk of unknown long-term health effects. ‘This experiment exposes healthy normal children to risks of gene editing for no real necessary benefit,’ says bioethicist Julian Savulescu.” For those who are not formal students of bioethics, Julian Savulescu is hardly a Luddite or a God-fearer who is nervous about new technologies. He’s right, in this case.
Note the concern about “leapfogging” discussions of the ethics. This point is also well-taken. Scientists have been arguing that broad, public discussion of the ethics of human gene editing is urgently needed. On March 29 of this year, your correspondent—who is scrambling to catch up even to this week’s commentary—posted about two such arguments.
But the genie is out of the bottle, and things are moving faster than most folks can keep up with. The work reported this week was from China, but was not part of some Chinese government effort—it appears to have been entirely on private, intrepid initiative. As a writer in the San Diego Union Tribune wrote this week, Pandora’s box has been opened and can’t be closed.
This week’s announcement came at the international conference on gene editing, in Hong Kong. The two days’-plus of proceedings, including a session with the scientist who did the work discussed here, can be accessed online. The conference main web page is here. The proceedings archived on webcast appear to be accessible here. A summary of the Q+A with the scientist is here.
Oh, BTW—at the end of the Nature summary linked at the top of this post was a chance to vote on whether this application of gene editing was justified. I voted “no,” as did 82% of respondents at the time I voted. That left “yes” at 18%.
18%?? For real?