Older Embryos Can Survive Stem-cell Extraction

Mouse study suggests stem-cell work could be made more efficient.

US researchers say they have improved the technique by which stem cells can be coaxed from an embryo without harming it.

The technique has been used only on mouse embryos and is still being refined. But it might improve attempts to make embryonic stem (ES) cell lines without destroying human embryos.

Researchers are keen to create human ES cells because they can give rise to many different tissue types that could help cure diseases. Extracting the cells usually kills the embryo, which some find morally unacceptable.