The meeting, organised by the US's National Academy of Medicine and National Academy of Sciences, and the UK's Royal Society, was held at the National Academy of Sciences in Washington.
Whilst this is not the first time that experts have met to discuss the use of the CRISPR/Cas9 genome editing technique in human embryos, this is the first occasion where representatives of the scientific and industrial community, regulatory and funding bodies, and patient advocacy groups have come together to develop a framework to govern such experiments.
Professor Kay Davies at the University of Oxford, and one of the commission's two co-chairs, opened the meeting by stating that it was intended to initiate discussion around the technology, saying that 'the commission has made no conclusions yet, and it would be a mistake for anyone to leave here today thinking otherwise.'
Prior guidelines around embryo editing, published after the meeting of the National Academies of Science, Engineering and Medicine in 2017, were open to ambiguous interpretation. Indeed, the controversial announcement by He Jiankui last year that he had used the technology to edit the genomes of twin baby girls (see BioNews 977) was made more shocking to the scientific community by his claim that he was acting within the recommendations outlined in the 2017 report.
'We can't leave things as they were in 2017,' said Dr Victor Dzau, president of the National Academy of Medicine. 'There are still outstanding questions about what should and should not be done. There needs to be a lot more clarity about the circumstances under which embryo editing would be acceptable.'
Many of the representatives in attendance called for a complete moratorium on germline editing for clinical use at the present time. 'We currently do not, cannot and will not support gene editing in human embryos', said Carrie Wolinetz, acting chief of staff and associate director for science policy at the US National Institutes of Health.
Sarah Norcross, director of the Progress Educational Trust (the charity which publishes BioNews) addressed the commission, offering an idea of how genome editing could be incorporated into the UK's reproductive regulatory framework in future.
She suggested the technology's use could be regulated by the Human Fertilisation and Embryology Authority: 'Clinics would need a special license to genome edit, and then need another license for each case.'
'An embryo with an edited genome might become a "permitted embryo." It could be used to establish a pregnancy, to avoid "serious disease," or similar wording,' she said.
Whether or not the commission chooses to adopt a full ban remains to be seen - an alternative would be to allow clinical germline editing to proceed but only under strict conditions.
If this is the case then it is expected that the publication of the commission's report next year will provide a framework outlining exactly when germline editing - that is, altering the genomes of human cells that can be passed on to future generations - might be feasible and appropriate, along with a practical framework regarding preliminary experiments and validations.
National governments and governing bodies could use this to either establish regulations or prohibit embryo editing entirely. Whether all countries would adopt such practices is not yet known.
The meeting also included a short public comment period, which briefly addressed a range of issues including religious considerations and the commercialisation of embryo editing techniques.
A second meeting of the commission is anticipated for Spring 2020, along with the publication of their report.