Researchers at Forsyth Institute and Harvard University have discovered how we develop the left and right sides of our bodies. When the embryo consists of just four cells, an electrical charge occurs that switches on the genes that tell left from right. They discovered a tiny on pump on the surface of the cells that let's the embryo distinguish left from right.
When the researchers used drugs to disable the pump, the cells developed into organs that lacked the normal left-right configuration.
Further, the researchers discovered that when a salamander's leg is cut off, the wound actually emits a distinct electrical field that controls the formation of the new limb. Researchers were then able to apply this concept and have a mouse generate a new limb.
So... some day we may use this knowledge to heal humans.