Public Comment

A ban, not a moratorium, on human embryo modification

Stuart Newman and Tina Stevens
Friday June 28, 2019 - 05:22:00 PM

A twin birth in China last October raised ominous questions. The baby girls had been genetically edited as embryos, with the untested methods providing no confidence in healthy outcomes. The subsequent fallout has been confusing: a blue-ribbon group of scientists and ethicists sent a letter to the Secretary of Health and Human Services in late April recommending a moratorium, following a similar call in the scientific journal Nature. In both cases, the door was left open to clinical use if and when relevant stakeholders are satisfied it should proceed. And if the federal government won’t fund it, the tax-payer supported California Institute of Regenerative Medicine (CIRM) could.

When the relevant science (developmental biology) is considered, however, it becomes evident that embryo modification cannot proceed safely. Time-buying measures such as moratoria are simply strategies to deny this reality and enable its eventual implementation. But the question of whether embryos can be safely engineered has long been settled: they cannot. This is clear from experiments on animal embryos, where altered genes are seen to behave in unpredicted ways, and in human population studies, where genetic mutations that had been found to cause disease in some individuals or groups turned out to be perfectly harmless in others. 

There are two kinds of genetic engineering of animals such as humans: somatic and embryonic. Somatic modification is modular, meaning it affects limited tissues or organs in an existing person who is ill. We take no issue with somatic modification provided it is carefully monitored as to medical need and conflicting commercial interests. With existing methods of embryo engineering, however, changes made, including mistakes, will be passed on to future generations via the reproductive cells or germline. In fact, every cell in the body of the new individual is affected, making that person something different from what they would have been without the intervention. By this measure, the engineered person is less a patient and more an experimental organism, not being treated by a medical doctor, but being designed by a scientist. 

Entrepreneurial scientists have eased the way to acceptance of embryonic editing by downplaying technical problems and by vague reassurances that they will not go too far, too fast. Yet they never explain what they mean by this. Members of the U.S. scientific and bioentrepreneurial community, including several at Stanford and UC Berkeley, knew about the work of their colleague in China but said nothing publicly, willing to have human embryo research move forward to the extent permitted here and elsewhere. A temporary moratorium on embryo engineering for full-term birth won’t stop laboratory research in this field. In the absence of a true ban any technical advance will be used to promote public acceptance of what is in essence a form of human experimentation. 

Other unsettling questions either minimized or ignored by industry-led discussion relate to health hazards to the producers of the raw materials required by these technologies. These are young egg providers, or as we might know them, our daughters, nieces and granddaughters. The long-term reproductive health of young women who undergo egg harvesting for this research is poorly understood. Nor is it clear that egg “donors” are given adequate information to know how their eggs will be used. 

Whatever line existed between academic research and commerce has worn thin. Researchers at universities and institutes who were once relatively shielded from business interests now sit on the boards of and own shares in biotech companies that are major sources of scientific funding and infrastructure. Scientists who overstep cultural norms or federal restriction rarely suffer consequences beyond the loss of their federal funding. In the U.S. private corporations and state agencies like CIRM can define their own acceptable practices regarding egg procurement and embryo engineering. Thus, how these entities define too far, too fast, is completely subjective -- a recipe for human disaster. 

There is no limit to the present and future havoc an overly enthusiastic researcher might wreak. The scientist who bioengineered the babies in China may have affected their intelligence or shortened their lives in the process of attempting to prevent HIV. Another geneticist may next decide to do this on purpose or make other errors. The faster science and technology progress, the greater the potential for misuse. 

We must ban, not simply pause embryonic gene editing before someone decides to forge the very biological nature of future generations, threatening their health and hijacking their identities before they are even born. 


The writers are, respectively, Stuart Newman Ph.D, professor at New York Medical College, Department of Cell Biology and Anatomy, and Tina Stevens Ph.D, lecturer emerita at San Francisco State University, Department of History. They are the authors of Biotech Juggernaut: Hope, Hype and Hidden Agendas of Entrepreneurial Bioscience (Routledge). ___________________________________