Josephine Quintavalle, from the pro-life group Comment on Reproductive Ethics (Core), released this statement on what she called a "sad, sad day for both science and ethics":
It is hard not to feel despair that so many elected members of Parliament could agree to such a dangerous and unethical re-writing of human biology, no matter how virtuous the end objective of creating children without mitochondrial disease.
We have always argued in favour of seeking cures for mitochondrial disease but research applications in the United Kingdom will be aimed not at cures, but rather at creating a different kind of human embryo hopefully not carrying the condition.
MPs have voted in favour of a ground-breaking but controversial technique that could see IVF babies conceived with DNA from three people.
A vote on three-parent babies, taking place today, could determine paediatric nurse Rachel Steel's chances of having her own healthy kids.
The parents of a baby with a life-limiting disorder say their future happiness will be decided by today's three-parent family vote.