Researchers and ethicists, including the scientist who pioneered and patented CRISPR gene-editing technology, are calling for a global moratorium on human germline editing – changes made to inherited DNA, the genetic material in sperm, eggs or embryos that can be passed on to the next generation.
The ban would not apply to genetic editing done only for research purposes or to the editing of cells to treat diseases.
“We do not mean a permanent ban,” wrote Feng Zhang, a molecular biologist and member of the Broad Institute, which holds the patent for the CRISPR-Cas9 genome editing tools; Emmanuelle Charpentier, founder and director of the Max Planck Unit for the Science of Pathogens; and their co-authors from seven nations in a commentary published Wednesday in the journal Nature.
Instead, they call for the establishment of an “international framework” in which nations retain “the right to make their own decisions” while committing to outlaw all work involving edits of inherited DNA unless conditions are met.
Fallout after reports of genetically modified babies
The moratorium is needed, they say, largely due to the Chinese scientist who claimed to have made gene edits when creating two AIDS-resistant babies last year. He Jiankui, whose work has been widely condemned, reportedly made a change to their genomes that could have unforeseen consequences, including increasing the babies’ intelligence and raising their risk of death from other viral infections, according to the authors of the proposal.
Overall, the societal impacts of human germline editing could be considerable, they wrote. “Individuals with genetic differences or disabilities can experience stigmatization and discrimination. Parents could be put under powerful peer and marketing pressure to enhance their children.”
The idea of “redesigning the fundamental biology of humans” might be “morally troubling” to some, while “unequal access to the technology could increase inequality,” they say. Other risks include dividing humans into subspecies and future generations with potentially harmful mutations that “cannot be removed from the gene pool unless all carriers agree to forgo having children, or to use genetic procedures to ensure that they do not transmit the mutation to their children.”
Moratorium might not be best solution, critics say
Wholesale endorsement of the proposal is not forthcoming from the wider scientific community.
“Although we do not agree that a moratorium is necessarily the best way to navigate this issue in the short term, it is clear that we do not yet fully understand the risks or benefits of this powerful technology, and finding the right governance approach is critical,” Beth Thompson, head of UK and EU Policy at the Wellcome Trust, a biomedical research nonprofit, told the Science Media Centre.
Thompson, who did not contribute the new commentary, added that her organization agrees with many of the principles outlined in the commentary. “There must be robust national laws shaped by public consultations and informed by the latest science,” she said.
A more critical view was expressed by Helen O’Neill, program director of reproductive science and women’s health at University College London. She told the Science Media Centre that the commentary “serves to ignore rather than reiterate that a global ban is already in existence and only attempts to address what would happen in the case of another extreme scientist.”
“Currently, there are (as there was in China) legal and ethical measures in place globally which regulate the use of gametes and embryos,” said O’Neill, who did not work on the proposal. “Let’s not forget that He Jiankui broke many rules, and was aware of this by choosing to do his work outside of the auspices of the university (and taking unpaid leave).”
Sarah Norcross, director of the Progress Educational Trust, a nonprofit promoting public understanding of reproductive and genetic science, told the Science Media Centre that a new moratorium “is neither necessary nor useful.”
A moratorium would not have deterred Jiankui, said Norcross, who also had no role in the commentary. She added that he “acted secretively and in breach of a clear scientific consensus that germline genome editing should not be used in the clinic at this time.” Even more, she believes that his practices were “scientifically and ethically unsound in so many different ways, that they would have been wrong regardless of whether or not they involved germline genome editing.”
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Her nonprofit, which frequently organizes public events, has found “that people do not worry specifically about changing the germline,” she said. “They are more concerned with whether or not specific applications of genome editing are medically warranted.”
O’Neill was skeptical for yet another reason: “There has never been a broad societal consensus about anything in any country, not even the allocation of human rights, so expecting this as a benchmark for clinical adoption of germline therapy is unrealistic.”
