So, the votes on the Human Fertilisation and Embryology Bill are taking place over the next couple of days, with the big one — hybrid embryos — happening today.
The BBC has summarised the key points on both sides of the debate:
What are the arguments in favour of this process?
Scientists who advocate the work say the cells would allow them to study how genetic defects, which cause diseases such as Parkinson’s, develop.
They also say that stem cells’ ability to develop into different tissues mean it could be possible to use cells formed in this process to cure diseases.
Using animal eggs would enable scientists to overcome the problem that human eggs are in short supply.
What are the arguments against?
Opponents say it is tampering with nature, and is unethical.
On the one hand we have a set of reasoned arguments detailing specific predicted health benefits for thousands of people, and on the other we have “eewwww!”.
I really wish people would stop conflating their own squeamishness with their ethical position; it clouds important issues, like this, where the ethical position is surely the one that saves lives.