human embryo

An international team has put human cells into monkey embryos in hopes of finding new ways to produce organs for transplantation. But some ethicists still worry about how such research could go wrong.

Aiming to find a cheaper, easier way than IVF to ensure human embryos are healthy before implantation, researchers paid women to be inseminated, then flushed the embryos from their wombs for analysis.

Researchers hope these "embryoids" could provide crucial new insights into how to treat infertility and prevent miscarriages, birth defects and many diseases. But they stir ethical concerns.

A Moscow scientist claims he has a safe way of editing genes in human embryos — a method that could protect resulting babies from being infected with HIV. Approval of the experiment seems unlikely.

An international group of 18 prominent scientists and bioethicists is calling for countries around the world to impose a moratorium on the creation of babies whose genes have been altered in the lab.

NPR gets exclusive access to a lab in Portland, Ore., where scientists have begun editing the DNA in human embryos to try to prevent genetic diseases.

In experimental embryos, scientists were able to repair the gene that causes a serious heart disorder. More research is needed to confirm the method would produce healthy babies, they say.

A Swedish biologist wants to change the genes of healthy human embryos to find ways to treat infertility and other diseases. The experiments intensify ethical questions about genetic engineering.