Scientists repair gene defect in embryo

WASHINGTON - In a first, researchers safely repaired a disease-causing gene in human embryos, targeting a heart defect best known for killing young athletes - a big step toward some day preventing a list of inherited diseases.

In a surprising discovery, the research team led by Oregon Health& Science University reported on Wednesday that embryos can help fix themselves if scientists jumpstart the process early enough.

It was laboratory research only, nowhere near ready to be tried in a pregnancy. But it suggests that scientists might be able to alter DNA in a way that protects not just one baby from a disease that runs in the family, but his or her offspring as well. And that raises ethical questions.