Summary: Protein hyper-interleukin-6, a "designer protein" that has to be produced via genetic engineering, enabled a paralyzed mouse to walk again. Spinal cord injuries caused by sports or traffic accidents often result in permanent disabilities such as paraplegia.

The U.S. military thought it had cleared the decks when, on 9 July 1962, it heaved a 1.4-megaton nuclear bomb some 400 kilometers into space: Orbiting satellites were safely out of range of the blast. But in the months that followed the test, called Starfish Prime, satellites began to wink out one by one, including the world's first communications satellite, Telstar.

Imagine making your commute home, bracing yourself for the human tsunami that is sure to greet you when cutting through a busy train station. Only this time, instead of the din of a bustling crowd, you're met by an angelic chorus.