First UK Code of Practice for use of stem cell-based embryo models drawn up by University of Cambridge-led group
Any human stem cell-based embryo model will be prohibited from being transferred into the womb of a human or animal, or allowed to develop into a viable organism in the lab, under a new code of practice.
It has been drawn up by the University of Cambridge, in partnership with the Progress Educational Trust, and represents the first set of UK guidelines on the use of these three-dimensional biological structures.
They can be created in the lab to mimic aspects of early human development and, while not the same as human embryos, have raised ethical considerations.
But UK law does not currently explicitly regulate the use of stem-cell based embryo models (SCBEM), which has created uncertainty among scientists about legal and ethical boundaries that has held back research.
The new SCBEM Code of Practice is designed to provide researchers with clear guidance and oversight processes, bringing transparency to their work and reassurance to the public.
Under the code, a dedicated oversight committee will review each proposed research project.
The code also recognises that there must be a limit to how long embryo models can be grown in the lab. But since many types of embryo model are being developed, representing distinct developmental stages and developing at different rates, it is impossible to impose a single fixed limit. Instead, researchers will be asked to provide clear justification of the length of their experiments on a case-by-case basis.
The guidelines were developed by a working group from 13 UK institutions, also including the Babraham Institute. Members brought expertise in science, law, ethics and regulation.
“The new Code of Practice provides processes for decision-making in research using stem cell-based embryo models so that scientists can proceed confidently, while maintaining public trust in this vital area of research,” said group member Kathy Niakan, chair of Cambridge Reproduction and professor of reproductive physiology at Cambridge.
“Embryo models have huge potential and we want to realise this, while also limiting the risks. The new Code of Practice will allow stem cell-based embryo models to be grown in the lab long enough to gain meaningful biological understanding, but the code asks researchers to fully justify what they’re doing in scientific and ethical terms.”
The working group noted there is currently an “absence of evidence as to whether SCBEMs do, or do not, have the potential to develop into a viable entity”.
The models are created from stem cells to provide insights into critical early stages of human development that would otherwise be inaccessible to researchers. They can aid the study of early pregnancy loss and pregnancy disorders, congenital defects and the precursor events that affect adult human health and disease.
And their use could lead to new interventions for a range of conditions, potentially revolutionising treatments for recurrent miscarriage, understanding developmental disorders and improving the success rate of IVF.
There are significant limitations to clinical trials and the use of many medicines during pregnancy, so the use of models of early development could prove helpful in improving options for drug treatments during pregnancy.
Only limited studies are possible with actual human embryos but stem cell-based embryo models open new research avenues.
The Code of Practice says that neither area of research can or should replace the other for the foreseeable future.
While the code is not legislative, the team proposes that it should be adopted by UK researchers, funders, research organisations, professional societies and publishers.
It is hoped that its widespread adoption will set a precedent for reporting research utilising stem cell-based embryo models, while deterring the funding and publication of research that fails to meet its standards.
The code will also be reviewed regularly, since the research involving embryos models is developing rapidly.
“We are confident that the Code will enable the UK to continue to lead the world in research into early human development, while ensuring that this research is ethically robust,” said Prof Roger Sturmey, professor of reproductive medicine at Hull York Medical School and chair of the working group.
The code was informed by a public dialogue earlier this year exploring public attitudes towards research involving embryo models.
“Throughout the process of developing the Code of Practice, we’ve been keen to engage with as wide a range of stakeholders as possible, including researchers, experts in law and bioethics, regulators and funders,” said Christina Rozeik, programme manager of Cambridge Reproduction and member of the SCBEM Code of Practice project team.
“A public dialogue enabled us to include public voices during the development of the code, taking account of their hopes, concerns and sensitivities around research involving stem cell-based embryo models. Participants were excited by the potential of embryo model research, but also strongly supportive of oversight.”
Group member Dr Peter Rugg-Gunn, group leader and head of public engagement at the Babraham Institute, added: “Establishing this guidance takes stem cell-based embryo models out of the grey zone and onto more stable footing so we can fully explore their usefulness, while providing the essential reassurance that this research is being conducted carefully and with appropriate scrutiny.”
Professor Kathleen Liddell, of the University of Cambridge, was also among the working group. It included researchers and practitioners from the Babraham Institute, Biolawgy, Brighton and Sussex Medical School, the Centre of Medical Law and Ethics at King's College London, the Francis Crick Institute, Hull York Medical School, the Medical Research Council, Newcastle University, University College London, the University of Cambridge, the University of Edinburgh, the University of Exeter and the University of Manchester.