RNA

A newly discovered class of molecules plays an astonishingly powerful role in biology.

Deep in your DNA, a gene has gone haywire and is driving up the production of a protein that is messing with your body. Wouldn’t it be great to sift through all your 20,000-something genes, find the offender, and swat it like a fly? Fortunately, a new technique eventually could do just that.

Once thought to serve only as a bridge between genes and protein production, RNA is quickly shedding its reputation as being all brawn and no brain. RNA’s research renaissance is due in part to the recent discovery of a new class of genes called microRNAs (miRNAs). Rather than code for proteins, miRNAs serve as regulators—genetic trump cards that turn protein-coding genes off.