National Geographic News
January 25, 2005
Scientists have begun blurring the line between human and animal by producing chimeras�a hybrid creature that's part human, part animal.
Chinese scientists at the Shanghai Second Medical University in 2003 successfully fused human cells with rabbit eggs. The embryos were reportedly the first human-animal chimeras successfully created. They were allowed to develop for several days in a laboratory dish before the scientists destroyed the embryos to harvest their stem cells.
In Minnesota last year researchers at the Mayo Clinic created pigs with human blood flowing through their bodies.
Watching how human cells mature and interact in a living creature may also lead to the discoveries of new medical treatments.