fter getting the data back from the very first experiment at her new job, Rosalyn Ram, a lab technician at the University of Texas Southwestern Medical Center at Dallas, was convinced she had messed something up. The results were decidedly "weird," she recalls. Her lab heads, the husband-and-wife research duo David Corey and Bethany Janowski, had already shown that synthetic DNA molecules with protein-like backbones, known as peptide nucleic acids, could block gene transcription. And as a long shot, in October 2004 they had tasked the new lab tech with trying to do the same with small RNA molecules, fully expecting it not to work.
But it did work: Like the peptide nucleic acids, the RNAs targeted to the same promoter also silenced gene expression at the level of transcription. "When [Ram] saw the silencing, she thought she had done something wrong," says Janowski. "She didn't want ...
