The creation of babies whose DNA has been altered to give them what parents perceive to be the best chances in life has received a cautious green light in a landmark report from a leading UK ethics body.

The Nuffield Council on Bioethics said that changing the DNA of a human embryo could be “morally permissible” if it was in the future child’s interests and did not add to the kinds of inequalities that already divide society.



The report does not call for a change in UK law to permit genetically altered babies, but instead urges research into the safety and effectiveness of the approach, its societal impact, and a widespread debate of its implications.

“It is our view that genome editing is not morally unacceptable in itself,” said Karen Yeung, chair of the Nuffield working group and professor of law, ethics and informatics at the University of Birmingham. “There is no reason to rule it out in principle.”

But the report drew immediate criticism from some quarters, with one lobby group accusing the authors of opening the door to the unrestricted use of heritable genetic engineering, and an age of genetic haves and have-nots.

Recent advances in genetic technology have given scientists the tools to rewrite the DNA bound up in living cells, letter by letter. With the procedures in hand, scientists can in principle tweak the genetic code in sperm, eggs and embryos, and change dramatically how future children develop.

While laws in the UK and some other countries currently ban the creation of genetically altered babies, a handful of experiments around the world have shown that DNA editing could, in principle, prevent children from inheriting serious diseases caused by faulty genes.

The prospect of modifying genes in human embryos has long been controversial though. For a start, the procedure has yet to be proven safe. In a study published in Nature Biotechnology on Monday, British researchers found that the most popular tool for genome editing, Crispr-Cas9, caused more damage to DNA than previously thought. If the scientists are right, gene editing could disrupt healthy genes when it is meant only to fix faulty ones.

Another consideration is that any changes made to an embryo’s DNA would affect all of its cells, including the sperm or eggs, meaning that genetic modifications would be passed down to all future generations. Also, in the vast majority of cases alternative procedures, such as preimplantation genetic testing, can be used to screen embryos for harmful DNA.

DNA editing also raises the possibility of “designer babies”, where the genetic code of embryos created through standard IVF is rewritten so that children have traits the parents find desirable. The Nuffield report does not rule out any specific uses of genome editing, but says that to be ethical, any applications must follow the principles of being in the child’s interests, and have no ill-effects for society.

Jackie Leach Scully, professor of social ethics and bioethics at Newcastle University, and a co-author on the report, said heritable genome editing may one day become an option for parents “to try and secure what they think is the best start in life” for their future children.

But she warned that there could be unintended consequences if the law were changed to allow gene editing of human embryos. While the technology could potentially reduce the number of people affected by certain genetic disorders, it could leave those with the diseases feeling more marginalised and with less medical support.

The report urges government to set up a new body to ensure that as many voices as possible are involved in public discussions about what should and should not be permissible. “We are very clear that what we need to have is as wide a discussion about this issue as possible,” Leach Scully said. In the event that the law is changed, gene editing of human embryos should be considered on a case-by-case basis by the fertility regulator, the Human Fertilisation and Embryology Authority, the report adds.

George Church, a geneticist at Harvard University who was not involved in the report, said he agreed with the report’s guiding principle that gene editing “should not be expected to increase disadvantage, discrimination, or division in society,” adding that this would be aided by lower costs and better public dialogue and education. Making changes to common gene variants in sperm and eggs could save roughly 5% of babies from painful diseases he said.

But Marcy Darnovsky at the Center for Genetics and Society in California said that the report recognised that if reproductive gene editing was permitted, it would be used for enhancement and cosmetic purposes. “They dispense with the usual pretence that this could – or, in their estimation, should – be prevented. They acknowledge that this may worsen inequality and social division, but don’t believe that should stand in the way. In practical terms, they have thrown down a red carpet for unrestricted use of inheritable genetic engineering, and a gilded age in which some are treated as genetic ‘haves’ and the rest of us as ‘have-nots’.”