A pathologist by training, Joung has spent much of the intervening decade designing ever-more sensitive methods for detecting these so-called off-target effects and finding ways to minimize the chances they occur. Such methods have, in the last two years, proved pivotal in the decisions by regulators to approve the first CRISPR-based medicine \u2014\u00a0an infusion of gene-edited blood stem cells called Casgevy \u2014 for treating sickle cell disease. Which is why, on Wednesday, at a gathering of a few dozen academics, physicians, industry experts, disease advocates, and religious leaders, many were surprised to hear Joung say that science was still a long, long way from having similar sorts of visibility into what happens inside a human embryo when it\u2019s gene-edited.\u00a0<\/p>\n
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\t\t\t\t \u201cIt\u2019s very, very challenging, if not impossible,\u201d Joung said to those gathered in Washington, D.C. for the meeting, which was organized by the American Society of Gene & Cell Therapy, the International Society of Cell & Gene Therapy and the Alliance for Regenerative Medicine.\u00a0<\/p>\n Joung, currently on leave from Massachusetts General Hospital while he works at Arena Bioworks<\/a>, offered one of many perspectives represented at the one-day event, dubbed \u201cAdvancing Guardrails on Heritable Human Editing.\u201d The meeting was an attempt to pick up where the National Academies and the Royal Society left off two years ago in London, where the Third International Summit on Human Genome Editing closed with a call for more debate about whether the technique should ever be used, even as organizers encouraged research in the area of heritable editing to push forward<\/a>.\u00a0<\/p>\n Unlike so-called somatic gene editing, where one type of cell or tissue (the one where a mutation is wreaking the most havoc and causing disease) is targeted for modification, editing an embryo would mean all the cells of the resulting person would carry the genetic change. Different cells express different sets of genes, so if CRISPR screwed up, it would be hard to predict what the impact of that error would be in the brain versus, say, the heart. That\u2019s even assuming there isn\u2019t mosaicism \u2014 where CRISPR stays active after an embryo starts dividing, causing different types of mutations in the cells that give rise to different types of tissues.\u00a0<\/p>\n This is what happened to the twin girls born in 2018 as part of the now-globally renounced experiment undertaken by He Jiankui to make the first CRISPR children. In addition to all the ethical<\/a> and legal issues<\/a> with how the trial was conducted, sequencing showed the babies\u2019 cells carried a mess of random edits<\/a>, the health consequences of which are still unknown today. At the end of the 2nd International Summit on Human Genome Editing in Hong Kong, where He presented this data, organizers of the meeting condemned the experiment but said it showed \u201cthat it is time to define a rigorous, responsible translational pathway\u201d toward trials that would test the impact of using CRISPR and other tools to edit the germline \u2014 the DNA of sperm, eggs, or embryos.<\/p>\n \t\t\t \t\t\t\t\t\tSetting aside the thorniest issues around CRISPR babies, scientists say embryo-editing research should proceed<\/a><\/p>\n But scientists still lack the tools necessary for understanding what kinds of risks germline editing poses to future generations of humans, Joung said on Wednesday. \u201cI don\u2019t think we can define a regulatory pathway at this point because we don\u2019t even have the assays or the experience to try to account for these safety-related issues,\u201d he said. \u201cAt present, and for some fairly lengthy period of time going forward, we\u2019re not going to have great insights into what the potential safety issues are for doing this type of editing.\u201d<\/p>\n Notably, at this meeting, there were people in the room from the biotech industry, like Joung, who is also a co-founder of Editas Medicine and Beam Therapeutics, among other companies. That was important to Tim Hunt, head of the Alliance for Regenerative Medicine and one of the organizers. Back when he was himself working at Editas<\/a>, Hunt rounded up executives from all the other major gene-editing companies working to bring the technology to patients \u2014 CRISPR Therapeutics, Intellia Therapeutics, Sangamo Therapeutics \u2014 and pitched a panel to the organizers of the 2018 Summit in Hong Kong. It was rejected. Twice. \u201cNot enough time in the schedule,\u201d Hunt said he was told.\u00a0<\/p>\n That\u2019s not uncommon for the National Academies, which tends to center science from academic institutions and is sensitive to potential conflicts of interest. But it still left a gap into which speculation about commercial interest in heritable human editing flowed. On Wednesday, those in attendance made it clear that altering the DNA of embryos is not a treatment modality the biotech industry is setting its sights on.\u00a0<\/p>\n \u201cIt\u2019s just completely infeasible from a financial perspective as opposed to a therapeutic that allows you to treat many, many patients,\u201d said Devyn Smith, CEO of Arbor Biotechnologies, which is developing CRISPR treatments for rare diseases<\/a>. But aside from the economics, Smith said it was hard to imagine diseases that could only be addressed through embryo editing. \u201cI can\u2019t think of a single indication that would be justified.\u201d\u00a0<\/p>\n This was frustrating to some of the rare disease advocates in the room. Sierra Phillips, whose son Jack was born with Warsaw Breakage Syndrome \u2014 an ultra-rare inherited developmental disorder \u2014 said if embryo editing to fix their mutations had been available during her experience with IVF, she would have opted for it, \u201c1,000 percent.\u201d \u201cDon\u2019t let fear of this being hard, or expensive, or a long timeline, get in the way,\u201d she urged the industry representatives. \u201cWe don\u2019t know if we don\u2019t try.\u201d<\/p>\n But Carrie Wolinetz, a former senior adviser to the director of the National Institutes of Health, who lost a child to a rare genetic disease 12 years ago, cautioned against moving to cross the embryo-editing Rubicon, maybe ever. \u201cNothing I\u2019ve heard today has convinced me we can get to the safety standard that I would personally feel comfortable with,\u201d she said.<\/p>\n For people like Wolinetz, who\u2019ve been speaking and thinking about some of these issues for more than a decade, there was a certain sense of d\u00e9j\u00e0 vu in spending a day immersed in the latest state of the science and having that drive discussions about when or how embryo editing could move into human studies. \u201cIn all these years of conversations, we dance around the question of should we do this at all?\u201d she said. \u201cWe call the question and then don\u2019t really answer it.\u201c<\/p>\n That\u2019s something Benjamin Hurlbut, a biomedical historian at the University of Arizona, is hoping to change with an organization he co-founded called the Global Observatory for Genome Editing<\/a>. In May, it will be convening a three-day event in Boston that\u2019s open to the public and will take a human-first, rather than a technology-centric approach to trying to answer the question of \u201cshould we?\u201d<\/p>\n![\"\"\/](\"https:\/\/www.statnews.com\/wp-content\/themes\/stat\/images\/home\/statplus.svg\")
\n\t\t\t\tA pariah in science, the \u2018CRISPR babies\u2019 researcher gains support from a U.S. cryptocurrency entrepreneur<\/a><\/p>\n![\"\"](\"https:\/\/www.europesays.com\/ie\/wp-content\/uploads\/2025\/09\/Photo-22-04-2022-14-12-26-768x432.jpg\")
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