What Good is a Scientific Meeting If You Dismiss the Science?

Posted by Jessica Cussins October 29, 2014
Biopolitical Times
Picture of monkey see, hear, and speak

I want to be wrong about this.

Based on the evidence hearing held by the UK Parliament’s Science and Technology Committee last week, it is apparent that there is ample enthusiasm among many in Parliament for changing the UK law against human germline modification to allow what’s called “mitochondrial donation” into fertility clinics. The technique would combine genetic material from two women and one man into a single embryo.

Perhaps naively, I am still shocked by the hubris of some proponents of this technique. I really thought that mounting evidence of the risks to resulting children would encourage more people to question the advisability of this path.

But if the upcoming Parliamentary vote isn’t informed by a more realistic approach, it seems likely that women will be offered this technique by their fertility specialists as early as next year, making the UK the only nation in the world to explicitly allow a form of human inheritable genetic modification. Importantly, this would not be attempted as a closely controlled clinical trial, but in the open market of the fertility industry (with guidance from the HFEA, but no required follow-up).

I sincerely hope that any children born via this technique do not have to pay the price for our desires and curiosity. To reiterate, I really want to be wrong about this. But unlike many at this “evidence hearing,” I cannot so easily dismiss the evidence.

Dr. Edward Morrow, an evolutionary biologist at the University of Sussex, was the sole panelist out of nine to raise a single concern about the state of the science. Dr. Morrow is hardly alone in his concerns; numerous scientists, fertility specialists (pg. 36), and public health advocates have questioned the safety and efficacy of these techniques. But Morrow’s fellow panelists were remarkably unmoved.

Every concern that was raised – either from Morrow or as a question from others in the room – was dismissed as a “theoretical concern.” This worked rhetorically to marginalize those urging caution, and to make the proponents the keepers of the “practical reality” of the matter. But the possible benefits of this technique are no less theoretical than the possible risks.

In fact, if you stack the evidence side by side, the chance that “mitochondrial donation” will actually lead to a healthy child seems like the greater leap of imagination.

Since the hearing at which he was effectively sidelined, Morrow has taken the trouble to enumerate some of the evidence for us. He has compiled numerous papers that highlight problems that can occur from mito-nuclear mismatch here. He has also provided a link to a new meta-analysis in the Journal of Evolutionary Biology that reviews 66 publications showing evidence of significant effects on a variety of traits from the interaction of the nucleus and the cytoplasm (which includes the mitochondria). What this all suggests is that if even a single one of the complex interactions that occur continuously between the nucleus and mitochondria are disrupted by “mitochondrial donation,” it could lead to a range of adverse outcomes in a resulting child.

At the hearing, Morrow’s claims were dismissed as being irrelevant to humans because they took place in inbred animal tests. But as Morrow pointed out, that is only the case in one of the studies reported above. Furthermore, there is all of the following additional evidence of possible health risks for resulting children, though they got no real attention at the meeting:

  • When pronuclear transfer was attempted in macaques, researchers couldn’t get a single embryo to implant; moreover, human embryos have been shown to be more sensitive to manipulations than macaque embryos
  • Even a tiny amount of carryover mutated mitochondria can lead to disease if preferentially replicated
  • Epigenetic harm can be caused by the removal and reinsertion of a nucleus from one egg or embryo into another
  • The reagents used could pose risks of toxicity to any resulting child

In addition to dismissing all this evidence, proponents relied on another move: they repeatedly downplayed the novelty of what is at stake.

Doug Turnbull, Director of the Wellcome Trust Centre for Mitochondrial Research, said that mismatches between nucleus and mitochondria can be compared to what happens naturally after multiple generations of not breeding with our cousins. Similarly, he insisted that the fact that there is no greater rate of disease among mixed-race babies tells us that this technique will be safe.

This kind of argument often pops up when new technologies are being promoted… Don’t worry! We’ve been doing (basically) this for forever! But at least in this case, the reassurance just isn’t based in reality. There is obviously a desire to placate a nervous public, but mixing DNA from three people into a single embryo is not the same as having a child with someone from a different ethnicity than you, and frankly, the notion that it could be is insensitive and insulting.

The patronizing effort to appease an “irrational,” “fearful” public extended to the HFEA’s Orwellian redefinition of genetic modification to specifically exclude mitochondrial manipulation techniques. The growing body of evidence that mitochondria impact traits means that despite the insistence of UK Chief Medical Officer Dame Sally Davies, this re-definition is neither “based on science” nor “reasonable.”  Morrow has a great post on this point here.

One participant at last week’s hearing asked about the fact that the UK would be going against international law if it moves ahead with this, pointing to international treaties stating that germline modification is incompatible with human dignity. Conservative MP Jane Ellison’s response avoided the question altogether. Rather than admitting to any concern about the UK becoming an outlier, she stressed that she is “extremely proud” that Britain is a “pathfinder” and “innovator” in this respect, and happily referred multiple times to the country’s “well-respected regulatory regime.”

The effort to change UK law in order to permit this biologically extreme procedure has been in the works for more than six years. There have certainly been a lot of documents, meetings and consultations. But I can’t help but wonder the same thing as Morrow:

Advances in genomic medicine are thrilling. I look forward to improved gene therapy treatments for consenting individuals who are currently suffering from diseases. But the deliberate creation of a new human being through an experimental technique that puts the most fundamental mechanisms of human biology at jeopardy is an entirely different calculus. Who will be responsible if this doesn’t work out?

Previously on Biopolitical Times: