When you put the clamp, the flat area and the cleaver together, you get a pretty good idea as to how Dicer works. We're now using this structural model to design experiments that might tell us what triggers Dicer into action.

I was kind of a nerdy, geeky type. And I loved math. People teased me about it. I felt pretty much like an outcast.

The impression sometimes created among the public is that scientists are working away in their labs, and maybe they're not always thinking about the implications of their work. But we are.

There's already a lot of active research going on using the Crispr technology to fix diseases like Duchenne muscular dystrophy or cystic fibrosis or Huntington's disease. They're all diseases that have known genetic causes, and we now have the technology that can repair those mutations to provide, we hope, patients with a normal life.

I think that for a lot of women there's a subtle but unfortunately effective discouragement of women pursuing the STEM fields.

Is it more ethical to edit embryos or to screen a lot of embryos and throw them away? I don't know the answer.