In the wake of UK’s green light to create human-animal embryos, scientists are protesting a bulletin from a Catholics Bishops Conference. The accusations hurled include “blatant inaccuracy” and “a radical violation of the truth.”
The technique that the Catholic Church highlights in its objections—combining human sperm and animal eggs—has nothing to do with using animal eggs to make human embryonic stem cells. (For that you swap out the nucleus in an animal egg with a human nucleus so that the elixir in the egg can elicit reprogramming.)
What both sides failed to say is that making sperm-egg chimeric embryos has actually been around and legal for decades as a means of assessing sperm’s viability, though it’s not done much now. Any fertilized eggs must be destroyed by the two-cell stage. (Try googling “hamster egg test”) The use of this test has been used to argue that making other sorts of human-animal embryos is ethical.
When the accusations are flying, everyone should still set out the facts.
Kudos to the Anglicans, who seem to me to have done a pretty good job of both explaining the science and their objections to the research. On the Lutheran side, a theological argument for chimeras also does an accurate job with the science.