Genetic modification of human embryos, though controversial is "essential", an international group of scientists and experts has said.
Members of a global network of stem cell researchers, bioethicists and policy experts, the Hinxton Group, released a statement saying the practice should be allowed to gain an understanding of the biology of early embryos.
But the group said it did not currently favour allowing genetically modified human babies to be born.
However, we acknowledge that when all safety, efficacy and governance needs are met, there may be morally acceptable uses of this technology in human reproduction, though further substantial discussion and debate will be required.
The group said that genetic modification of human embryos would bring "tremendous value to basic research" and said the science of gene-editing "will continue to progress rapidly".
The US refuses to fund any gene-editing technologies in human embryos.
America's National Institutes of Health (NIH) Director, Dr Francis Collins said in April that it "has been viewed almost universally as a line that should not be crossed".
But Debra Matthews, member of the Hinxton Group which met in Manchester last week, said despite deep moral disagreement on the subject"what is needed is not to stop all discussion, debate and research."