“We call for a global moratorium on all clinical uses of human germline editing — that is, changing heritable DNA (in sperm, eggs or embryos) to make genetically modified children,” the statement’s cosigners, who come from seven countries, wrote in the March 14 Nature.
Among the document’s signatories are CRISPR pioneers Feng Zhang of the Broad Institute of MIT and Harvard University and Emmanuelle Charpentier of the Max Planck Unit for the Science of Pathogens in Berlin.
The proposed moratorium would last about five years to give time for public education and debate about experiments. The delay would buy time for scientists to further test and refine CRISPR/Cas9 and other gene-editing tools to make them safer. The moratorium would also be voluntary, with each country pledging individually not to allow clinical trials for creating gene-edited children. Countries would make independent decisions on how long such a ban should last.
Gene editing of embryos, eggs and sperm would still be allowed for research purposes, but those then couldn’t be implanted in a woman’s uterus to establish pregnancy. Researchers could still use CRISPR/Cas9 and other gene editors to treat genetic diseases in adults and children, provided that any changes to those people’s DNA couldn’t be passed on to the next generation.
If those provisions seem familiar, they are.
Some researchers and ethicists have previously called making gene-edited babies “irresponsible.” A 2017 report commissioned by the U.S. National Academies of Sciences and Medicine (SN: 3/18/17, p. 7), as well as two international conferences on human genome editing in 2015 and 2018 (SN: 12/26/15, p. 12; SN: 12/22/18 & 1/5/19, p. 20), concluded that heritable gene editing is not ready for clinical use and should wait until the technology matures and there is public consensus on allowing it.
The big difference between those statements and the new call is the word “moratorium,” says bioethicist Alta Charo of the University of Wisconsin–Madison Law School. “In which case there is no real daylight, only a dictionary, between the authors of the Nature essay and the reports and summit statements made to date.”
Still, those previous admonitions didn’t stop Chinese scientist Jiankui He from editing DNA in embryos that resulted in the birth of two baby girls last year (SN Online: 11/28/18). Another woman was reportedly pregnant with a gene-edited baby at the time of He’s announcement in November. Other researchers knew about He’s plans and didn’t stop him.
“Given that both conferences declared as irresponsible this kind of experiment, but in fact, it went ahead, says that we needed a little bit more than just clucking at the end of things,” says molecular geneticist Paul Berg of Stanford University School of Medicine. “We needed to say a little bit more and actually call for a moratorium.”
Berg, who helped author the proposal, admits the new call is mostly a matter of semantics, but argues that the word choice does matter. “If everyone is saying it would be irresponsible to do it, then why not be explicit and say it should not be done?” he says.
Heads of the U.S. National Academies of Sciences and Medicine, in Washington, D.C., the U.S. National Institutes of Health, in Bethesda, Md., and the Royal Society in London published letters in support of the idea in the same issue of Nature…[ ]