The discovery that molecules called "small RNAs" control much of a gene's behavior--which may further research on cancer and stem cells--was named this year's top scientific achievement by the journal Science and its publisher, the American Association for the Advancement of Science (AAAS).

The importance of small RNAs, named the Breakthrough of the Year by Science's editors, leads their list of the top ten scientific developments in 2002. Science's Top Ten, chosen for their profound implications for society and the Advancement of science, appear in the journal's 20 December issue.

RNA was long thought to do little more than carry out DNA's commands for building proteins. The new picture, which came sharply into focus this year, shows small RNAs at the helm of many of the cell's genetic workings. In response, biologists are rethinking their understanding of the cell and its evolution, and uncovering new leads for treating diseases, such as cancer, caused by errors in the genome.

An array of recent studies has revealed how small RNAs can switch various genes on and off, and even trim away unwanted sections of DNA. One of the field's most electrifying discoveries this year was that small RNAs take charge during cell division, shepherding the material in chromosomes into the right configuration (Science Express 22 August 2002 and 5 September 2002).

This year's insights led to the tantalizing possibility that these processes, which include a type of cellular machinery known as "RNA interference," m
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Contact: Lisa Onaga
lonaga@aaas.org
202-326-7088
American Association for the Advancement of Science
19-Dec-2002