"I've never considered miscarriages as a source for stem cells."
Yep. But they have already been acquired and the lines have been replicated and so anyone who wishes to use them can obtain them.
There is no shortage of embryonic stem cells.
They have limited utility which is Mark's point. Adult stem cells and umbilical cells show more promise.
Mark says even if you're not religious, there's a limited pool of money, so it should go to the most promising treatments, and libs shouldn't use the issue to advance an agenda.