When scientists announced at a conference last week that they had created synthetic human embryos, it felt like something from Brave New World. News coverage conjured up images of scientists creating new human life in an unnatural way and then using it to conduct experiments.
The name applied to this latest advance is unfortunate, however, because the discovery represents a potentially significant breakthrough in the study of infertility and in particular, research into why embryos so often fail to implant in the uterus. While there are still unanswered questions about how these so-called synthetic embryos were created, misunderstandings and confusion could lead to bans that could derail important scientific work.
Whether the work is considered ethical and legal depends on whether these lab-grown clusters of cells have the potential to become human life. The scientists who created them, and others familiar with the work, say they can’t, and that’s part of what makes this an important discovery.
There are always legitimate ethical considerations when scientists work with the starting material of human life, concerns raised when scientists cloned a sheep in 1996 and later in the early 2000s, when they learned to make potential replacement tissue from discarded human embryos from fertility clinics.
But in an information vacuum, meaningful medical advances and legitimate ethical debates can easily get trampled on. That’s what happened with the earlier work on embryonic stem cells, prompting restrictions during the administration of President George W. Bush — banning the use of federal funding for research that destroyed human embryos, even if they were to be otherwise discarded.
Some states bar embryo research outright. Others, such as California, have allocated state funding, while some have allowed only research done with private funds. Taking away the prospect of federal funding has seriously discouraged research. In principle, these new entities — synthetic embryos — shouldn’t be subject to these same rules or ethical considerations if they are, as the researchers claim, not capable of developing past a primitive, mostly unstructured state.
Kenneth Zaret, director of the Penn Institute for Regenerative Medicine at the University of Pennsylvania, had heard the synthetic embryo talk at last week’s gathering of the International Society for Stem Cell Research and said the term is misleading. Although the entities created are derived from human cells, they don’t have the potential to become human life.
That’s what makes them useful for studying fertility without running afoul of existing bans, says Zaret, who suggests “embryo model” might be a better description of these entities. He notes that around one-third of embryos fail before or around the time of implantation in the uterus.
He said running lab tests with these models might improve the success rate of in vitro fertilization, during which multiple embryos are made and a few are chosen to be implanted.
Art Caplan, a bioethicist at the New York University Grossman School of Medicine, said the ethical acceptability and legal status of synthetic embryos would depend on how dissimilar they are to real, potentially viable embryos. The claimed lack of similarity is hard to evaluate, however, because the research was announced at a professional meeting rather than in a peer-reviewed paper. That leaves the findings open to speculation.
While a peer-reviewed paper is likely to be forthcoming, there might be political pressure to ban this research before the scientists have had a chance to make their case — and before ethicists have had a chance to fully weigh in. In this sensitive area, the scientists should have been more careful how they announced and publicized what they had created.
“They could be setting up potentially valuable research for failure,” Caplan said.
The possibility of crossing the line is there. Scientists have used related techniques to make embryos of mice and monkeys and watched them develop hearts and other organs. That’s why clear guidelines are so important.
Science has helped more people become parents over the last 30 years. We could be on the cusp of still more progress. But researchers need to remember that the way they disclose new discoveries and the language they use to describe them will influence the public reaction to their work. Scientists need to be upfront and clear about what they are doing and what they don’t yet know, or risk seeing their efforts squandered.
