Stanford Nobel Prize winner Paul Berg and many of the world’s leading CRISPR scientists and bioethicists on Wednesday called for a global moratorium on genetically modified babies.
In the most direct opposition yet to the new gene-editing technique in embryos, Berg joined with 18 other researchers from seven nations to urge a five-year pause on its use to allow time for deeper discussion of its societal and medical implications.
They scientists also offered a general outline of how to proceed, safely, if there is agreement about the criteria, standards, safety and medical need for DNA modification.
“It is not going to close down everything,” said Berg, a founding member of Stanford’s Department of Biochemistry and winner of the 1980 Nobel Prize. “It is like a yellow traffic light — to slow down, stop at the line and act prudently.”
Their call for the moratorium, published as a commentary in Wednesday’s issue of the journal Nature, follows the stunning news last November that a Chinese researcher altered the DNA of at least two embryos to create the world’s first genetically edited babies.
The Chinese physicist He Jiankui conducted his post-doctoral research at Stanford under one of the university’s top bioengineers. He discussed ethics with a Stanford bioethicist and even revealed his plans to a UC Berkeley geneticist.
He also managed to persuade a Chinese hospital and infertility clinic to participate in the illegal research.
An international moratorium might have encouraged these scientists to speak up, Berg said.
“This is a call that alerts the systems in all countries — and calls for each person to accept responsibility to oversee that it is not done in their country,” said Berg. “If we get to a point where a scientist wants to proceed, there is a process for getting approval at the very highest level.”
Other authors of the Nature paper include two creators of the CRISPR system, Emmanuelle Charpentier of the Max Planck Unit for the Science of Pathogens in Berlin and Feng Zhang of the Broad Institute of the Massachusetts Institute of Technology and Harvard.
But CRISPR biochemist Jennifer Doudna of UC Berkeley, who favors a different approach, did not sign the paper.
Rather than a moratorium, Doudna supports “strict regulation that precludes use” of germline editing until scientific, ethical, and societal issues are resolved, she said.
“A moratorium,” she said, “is of indefinite length and provides no pathway toward possible responsible use.”
Meanwhile, the U.S. National Academy of Medicine and the National Academy of Sciences are planning an international commission on the use of the technology. Although a 2017 report by these two agencies offered examples of unmet medical needs that might justify germline editing, more detailed guidelines are needed, scientists say.
Berg was the brains behind an earlier moratorium. Scientists gathered at the famed 1975 Asilomar Conference called for a slow-down on a so-called “gene splicing” technology until it was proven safe. After the creation of voluntary guidelines during the conference, scientists slowly continued with their research, which is now a mainstream tool of modern biotechnology.
“When scientists act responsibly, that generates a good deal of public trust,” he said.
While there have been other warnings about CRISPR’s misuse, he said, “this is a more explicit statement.”
CRISPR is a powerful technology that allows scientists to quickly target, delete or repair a dangerously mutated sequence of DNA in any gene. While other gene-editing tools have emerged in recent years, CRISPR holds the most promise for transforming genetic research and treatment.
There is little controversy over its use in some individuals to fix genes that are not heritable, especially when it comes to curing diseases like sickle cell anemia and cancer.
And the scientists agreed that the use of gene editing in basic research should continue, as long as cells are not used to create a pregnancy.
But there is anxiety over its use in embryos or reproductive cells — altering future generations of humans — until its safety and effectiveness is proven, and there is broad societal consensus about the appropriateness of its use. There is risk that CRISPR will be used to create designer babies with desirable physical traits and talents, Berg said.
The moratorium would not prevent rogue science, he conceded.
“There will be outliers. There will be people who want to be the first to successfully modify a human germline,” he said.
But for anyone who violates an international norm, “there is so much to be lost,” he said. “Hospitals close down. Physicians lose the right to practice medicine.”
“Peer pressure has a very strong influence on legitimate scientists,” he said. “It is very unlikely that there will be anyone but a renegade who will try it.”
Stanford scientist joins call for moratorium on gene-edited babies