I saw this headline on Google news, and found it somewhat disturbing: Mice succumb to HIV at last. From the article:

"Mouse cells are naturally resistant to HIV in many ways. Some of these barriers have been overcome by adding human genes to mouse cells."

Um... hooray for us, because we've genetically engineered mice so that they can contract a deadly disease that they would otherwise be immune to? And next on their list is figuring out ways to make the HIV virus spread even more quickly in the mice, so they can get sicker faster.

I understand the research significance, but still. It seems a bizarre thing to celebrate.