Aggregated News

Photograph of a newly formed embryo

Scientists have created living entities that resemble very primitive human embryos, the most advanced example of these structures yet created in a lab.

The researchers hope these creations, made from human embryonic stem cells, will provide crucial new insights into human development and lead to new ways to treat infertility and prevent miscarriages, birth defects and many diseases. The researchers say this is the first time scientists have created living models of human embryos with three-dimensional structures.

The researchers reported their findings Monday in a paper published in the journal Nature Cell Biology.

But the research is stirring debate about how far scientists should go in creating living models of human embryos, sometimes called embryoids.

"It's very exciting work," says Insoo Hyun, a bioethicist at the Case Western Reserve University and Harvard Medical School who was not involved in the research. "But it does send folks down the road to thinking very seriously about where the limits may be ethically for this work."

For decades, scientists have worked to understand some of the earliest steps that enable an embryo...