"We are cautiously optimistic that this particular strain will not be more severe than a normal seasonal flu outbreak, " Napolitano said.

CNN: The story

Ryuzo Yanagimachi, a biologist at the University of Hawaii, found that when he cloned a certain strain of mice prone to have diabetes, the clones would look normal at birth, but upon reaching puberty -- which, in mice, is after eight weeks -- they gained weight.

CNN: Cloning experts to tell House committee pros, cons