After IVF many couples donate their unused embryos for stem cell research
Scientists get embryos is therapeutic cloning
Merges cell (from patient who needs stem cell therapy) with donor egg
Growing
Scientists remove them from blastocyst
Grow them in nutrient-rich solution in petri dish
Stem cells divide several times
Scientists divide population to other dishes
After several months, there are millions of them
If they continue to grow without differentiating, it is a stem cell line
Can be frozen and shared between labs
Necessary for developing therapies