11.   Other abortion opponents are against the research because the embryos would have to be destroyed to conduct the research.

12.   Rabbit embryos have the human gene inserted immediately after fertilization, meaning they do not have to have repeated injections of the gene, Van Willingen added.

13.   Those embryos also had to be an uncompensated research gift from their fully informed parents.

14.   Whether a six-cell embryo has the moral status of a person is a matter of debate.