Now another group of scientists — this time from Britain — is seeking permission to conduct similar experiments, raising the stakes for the technology.
Kathy Niakan, a stem-cell researcher at the Francis Crick Institute in London, has told the country's regulators that her work will focus on trying to understand what genes are at play during the first few days after fertilization, according to a report in the Guardian. She would switch genes off and on to study how the modifications impacted the development of the cells that form the placenta.
“The knowledge we acquire will be very important for understanding how a healthy human embryo develops, and this will inform our understanding of the causes of miscarriage," Niakan explained.
The embryos would come from donations from couples who had undergone IVF treatment and would only be used for basic research. It would be illegal for them to be implanted in a woman and allowed to grow more than two weeks.
Several other British scientists spoke out in support of the research. Peter Braude, emeritus professor of obstetrics and gynecology at King's College London, said in a statement that the research "is about better understanding nature, not changing embryos for implantation.”
Sarah Chan, a fellow at the Usher Institute for Population Health Sciences and Informatics at the University of Edinburgh said that the news should be "cause of confidence, not concern."
"Genome-editing research undeniably has tremendous scientific potential, and U.K. scientists are poised to make a world-leading contribution to this exciting field. At the same time, we should be reassured to know that this work is being carried out under a robust regulatory scheme that ensures high scientific and ethical standards," Chan said.
The reaction from others in the scientific community, however, was one of alarm.
"This proposal is a troubling and provocative move," said Marcy Darnovsky, executive director of the Center for Genetics and Society. "Modifying the genes of human embryos is deeply controversial because it can be used for worthwhile research on the one hand, or to produce genetically modified human beings on the other. A global public conversation about preventing such misuses is just getting underway, and this proposal could short-circuit those deliberations."
Likewise, Georgetown University Medical Center associate professor Kevin T. FitzGerald said he hopes British authorities "will delay processing this request by the Francis Crick Institute until the broad, public engagement that is needed to help guide the use of this powerful research tool can be accomplished.”
Debate about so-called germline editing of eggs, sperm and embryos has been going on for decades, but it has come to a head in recent years with the development of a powerful new gene-editing technology called Crispr-Cas9 that can make extremely precise edits to DNA and which was used by the Chinese team and would be used by the British team.
Michael Werner, executive director of the Alliance for Regenerative Medicine, a D.C.-based group that has been leading calls for a moratorium on the technology, called the research "highly premature."
"We believe that this type of multi-stakeholder discussion is necessary before proceeding, given the significant issues and concerns related to human germline genome editing," he said.
A discussion is scheduled for Dec. 1-3 during the National Academy of Sciences and the National Academy of Medicine international summit here Washington, D.C.
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