Literal nightmares:

Jennifer Doudna has been among the most vocal of those calling for caution on what she sees as the inevitable march toward editing human genes. “It’s going to happen,” she told me the first time we met, in her office at Berkeley. […] … Her eyes narrowed, and she lowered her voice almost to a whisper. “I have never said this in public, but it will show you where my psyche is,” she said. “I had a dream recently, and in my dream” — she mentioned the name of a leading scientific researcher — “had come to see me and said, ‘I have somebody very powerful with me who I want you to meet, and I want you to explain to him how this technology functions.’ So I said, Sure, who is it? It was Adolf Hitler. I was really horrified, but I went into a room and there was Hitler. He had a pig face and I could only see him from behind and he was taking notes and he said, ‘I want to understand the uses and implications of this amazing technology.’ I woke up in a cold sweat. …