Jon Hamilton reports for NPR:
Three American scientists who made key discoveries about how living cells age have received the 2009 Nobel Prize in Physiology or Medicine.
The winners are Elizabeth Blackburn of the University of California, San Francisco; Carol W. Greider of Johns Hopkins University in Baltimore; and Jack Szostak of Massachusetts General Hospital in Boston.
The scientists all study telomeres — structures that act like caps on the ends of chromosomes and protect them when cells divide. Chromosomes are the long strands of DNA that contain a living creature’s genetic code.
Working in different labs, the scientists figured out how telomeres allow genes to be copied without losing any information, a process that delays the aging of cells.