The other line of research, with stem cells from embryos, has a different obstacle.
Another is that no cells would be taken from human embryos or fetuses.
Pregnancies have been reported from embryos stored for 16 years.
Stem cells used in research are from embryos created for fertility treatment.
But the problem was that cells from early embryos were not good for genetic engineering.
But there is as yet no evidence from embryos that this occurs in nature.
"But I thought you said the stem cells came from embryos?"
We must also make it clear that no tissue or cells from embryos in general may be used.
But scientists cannot use federal money to extract the stem cells from human embryos.
All the rest of the children were developed from embryos in the laboratories.