Ethical transgressions

For the past 40 years, international guidelines have prohibited research on lab-cultured human embryos more than 14 days old: At that point of development, the embryo develops the primitive streak, the precursor to the spinal cord and brain. But on Wednesday, the International Society for Stem Cell Research released new guidelines relaxing the 14-day limit.

The new rules note that, if a region has public support for such expanded research and local policies allow it, “a specialized scientific and ethical oversight process could weigh whether the scientific objectives necessitate and justify the time in culture beyond 14 days.”

The group’s previous guidelines, released in 2016, prohibited embryo research beyond 14 days.

Established in 1979, the 14-day rule received little pushback for decades because no one could keep a lab-grown embryo alive for more than four or five days. But in 2016, a research team at the University of Cambridge successfully mimicked the conditions within a mother’s womb to develop human embryos for 13 days, setting a new world record.

Scientists in favor of the new guidelines claim extending development past the two-week mark could lead to improved fertility treatments and a better understanding of what causes birth defects. The revisions also allow a deeper dive into novel forms of embryo research. For example, scientists recently constructed the first embryos made from both human and monkey cells, hoping one day to culture human transplant organs in animals.

Yet pro-life bioethics groups, which oppose any research on human embryos, counter that the extension has dangerous implications for our understanding of human dignity. Growing embryos for longer periods opens the door to creating fully developed babies in a laboratory. Matthew Eppinette, director of Trinity International University’s Center for Bioethics & Human Dignity, sees this as problematic because it eliminates the important bond formed between mother and child during gestation. “There’s a whole lot of mystery surrounding what goes on during pregnancy,” he said. “I can appreciate that scientists want to explore that, but learning about it by severing it seems very misguided.”

The new guidelines also pave the way for developing genetically enhanced babies. In some cases, those genetic changes would be passed down to offspring, Eppinette said.

James Sherley, associate scholar at the Charlotte Lozier Institute, pointed out that the 14-day rule itself is flawed, since it grants embryos moral standing at an arbitrary point in their biological development rather than at conception.

“If we ask the question, ‘When does an embryo gain moral standing,’ we’re not going to be on scientific grounds anymore,” Sherley said. “The moral question for humanity is ‘How should we treat other human beings? Just because embryos are weak and can’t fight for themselves, should we harm them for our own gain?’”

Eppinette borrows from Carter Snead’s What It Means To Be Human to explain society’s tendency to care less about the unborn. As healthy adults, we see ourselves as completely autonomous, forgetting our dependence on grocery stores for food, gas stations to fuel our cars, and family and friends for emotional support. “We rely on one another for care and support,” said Eppinette. “There’s probably no clearer example of that than the embryo or fetus’ dependence on its mother.”

The 14-day rule is protected by law in at least 12 countries, including Japan and the United Kingdom. France and Germany ban human embryo research altogether. The United States is one of five countries in which the rule acts as a guideline, but is not enshrined in law.

For embryo research, Sherley argued laws are necessary: “There will always be a scientist that will push the envelope until society says, ‘No, you can’t go further than that.’”