SNIPPETS of RNA that switch off disease-causing genes can now slip into cells unaided. This could help efforts to use RNA interference (RNAi) to treat diseases such as cancer and diabetes.
For a gene to be expressed as a protein, it must first be copied into messenger RNA (mRNA). RNAi blocks this process by sending in RNA snippets that bind to specific mRNAs.
To do this, the gene-blocking RNA must first get into the cell. A variety of elaborate strategies have been suggested as ways to get it there, such as attaching the blocking RNA to fragments of bacteria…



