International commission: go slow with heritable human genome editing

The international commission on heritable human genome editing (HHGE), formed by the US National Academies of Medicine and Science and the Royal Society of Great Britain, has issued it report.  The 224-page report is freely available for reading here, and a summary news report can be accessed here.

The upshot:  not too fast.  The commission’s 11 major recommendations, briefly reworded and rearranged in order, are:

  • Before attempting any pregnancy with a gene-edited human embryo, “a significant cohort” of edited human embryos should be studied in the laboratory to ensure that the desired gene edit(s) “can be performed with sufficiently high efficiency and precision to be clinically useful.”  (No attempt would be made to bring these embryos to birth, and they would exist solely for research purposes, after which they would be destroyed.)
  • This efficiency and precision have not been demonstrated yet, and “no attempt to establish a pregnancy” with an edited human embryo should be made until they have.
  • Even then, the attempt should come only after “extensive societal dialogue” within any country whose leaders are considering endorsing the attempt.  This dialogue would include medical and scientific concerns, which the report addresses, and also “societal and ethical issues that were beyond the Commission’s charge.”  (Your correspondent has just begun reading the report, so cannot say yet whether the Commission considered how to proceed if one country green-lights edited human pregnancies while others do not.)
  • The only conditions that should be considered for editing are those of a serious disease caused by a single gene abnormality, for which the prospective parents have a less than 25% chance of having an unaffected child using current preimplantation genetic diagnosis (PGD).  Further, the resulting edited gene would be common and non-disease causing in the general population, and no embryos without the diseased gene would be edited. (This would seriously limit the use of HHGE—not permitting it for genes that increase the risk of cancer, for example—but, like the first point, would also raise concerns for conservative ethicists who consider all human embryos, from conception, to be human beings with the right to life.  If you’re troubled by PGD in general, this recommendation won’t satisfy you.)
  • The above would need to be followed for every proposed “treatment” of genetic disease—there is no “one-size-fits-all” approach to setting up a regime for heritable gene editing in general.  (This would have the effect of limiting the “industrialization” of HHGE, it appears.)
  • The actual transfer of an edited embryo to a woman’s uterus should be subject to (future) “rigorous” regulatory review and approval—that is, the edited embryo would be checked, in the laboratory, before transfer, to be sure that the edit had succeeded.   After transfer and through pregnancy, birth, and the life of the individual, close medical monitoring would be mandatory to learn what medical problems may have arisen.
  • A potential work-around should be studied in the laboratory: making human eggs and sperm from stem cells, with the intent of being able to use them for in vitro fertilization to give rise to an embryo without the abnormal gene.  However, the Commission recognizes that there are other canned worms, so to speak, to be dealt with here—such as whether this approach to begetting children is ethical at all, apart from any use of gene editing.
  • Any country embarking on HHGE in actual pregnancies should first put in place “mechanisms and competent regulatory bodies” to oversee standards and adherence to them, publication of results, and oversight in general.
  • An International Scientific Advisory Panel should be established in advance to oversee the progress of the science overall, before pregnancies are attempted—essentially, a single point of review to prevent intrepid scientists from “going rogue,” as it were.
  • An international body (presumably a different one from the above) with appropriate expertise should review every new proposed medical application of HHGE before pregnancies with the relevantly-edited embryos are established.  So, presumably, attempts to edit the gene for Huntington’s disease would be assessed separately from attempts to edit the gene for sickle cell anemia, for example.
  • An international mechanism should be established to adjudicate cases of alleged deviation from received guidelines or standards, and its’ results should be transmitted to individual governments and publicly released.

It looks like a careful report, welcome in its caution, although, as noted, those who hold that human life begins at conception will still likely object to the endorsement to continue with laboratory-based research.  “Just say no” to the prospect of HHGE—a position your current correspondent has consistently advocated on this topic—does not appear to be in view.  One might also be forgiven for skepticism over the effectiveness of any international body, given the controversies that arise from our existing international bodies for medicine and health, not to mention other endeavors.  Some such efforts, such as the regulatory harmonization of human clinical trials and drug development that governs the US, the EU, and Japan, work pretty well, but arguably are limited.

It is also worth mention that the California Institute of Regenerative Medicine (CIRM), established with Proposition 71 in 2004, ostensibly to translate embryonic stem cell research into cures (with creation and destruction of human embryos for the purpose), is proposed for renewed public funding in California with Proposition 14 in this November’s election.  Nothing approaching a cure was achieved under the CIRM, and even proponents of human embryonic stem cell research argue a renewal is unnecessary, because there is plenty of private money supporting related work already.  Further, the CIRM came under charges of insider dealing, because it needed to draw its leaders from the small pool of experts who tended to have career or monetary interests in the field to begin with, raising repeated concerns about a conflict of interest.  Would such potential conflicts plague the national and international bodies proposed by the HHGE Commission?  (Full disclosure: your correspondent will eagerly vote “no on 14” on his mail-in ballot this fall.)

Finally, so-called “somatic” gene editing—a fundamentally ethical undertaking by which a person’s cells may be altered to make them into a treatment for disease—is here to stay, as are certain forms of gene therapy that don’t involve heritable changes.  Expect to hear about those more in the future; they are subject to standard human subject research concerns, and to justice concerns like the eventual costs of the treatment.  Those topics for another day.

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