Contents

19 December 2008
Vol 322, Issue 5909

About The Cover

Cover image expansion

COVER A metaphorical USB cable transmitting genetic information to "reprogram"cells symbolizes the Breakthrough of the Year for 2008. Advances in the burgeoning field of cellular reprogramming have brought scientists closer to the goal of using stem cells to better understand and someday treat disease. See the special section beginning on page 1766 . Image: Chris Bickel