Short hairpins to silence genes

Endogenous genes could soon be 'silenced' by engineered strands of hairpin-shaped RNA, giving hope for a novel approach in the treatment and prevention of disease. In the April 15 issue of Genes and Development, Patrick Paddison and colleagues from Cold Spring Harbor Laboratory, New York, hijacked a natural cellular mechanism by driving the expression of short strands of RNA that will form hairpins once transcribed; the hairpins then block the activity of specific genes in Drosophila, mouse and human cells.

The use of RNA to interfere with gene expression has become a growth industry since the finding that injecting double-stranded RNA corresponding to a specific gene into a nematode blocked the activity of the gene (Science 1998, 282:430-431); this relies on an enzyme that encounters the RNA and breaks it up into smaller pieces that act as small-interfering (si) RNAs. A complex of proteins then gathers...