RNA Interference: Does It Work?

In 2006, the Nobel Prize in Physiology or Medicine was awarded for work in RNA interference, also known as RNAi. Since then, this technology has been used to silence genes in research, and potentially it can be used in humans to stop specific-disease causing genes. But as the New York Times reports, drugs using this mechanism work differently than expected.

RNAi works to stop a gene's message as it is translated. As the dogma of molecular biology states, a gene of DNA is transcribed to a single stranded piece of RNA, and the RNA is processed and translated to become a protein. To interfere with this process, a small piece of double stranded RNA is broken up into pieces that can bind to other RNA molecules that then become degraded (more information here).

Theoretically, using these pieces of RNA can silence viruses. Viruses reproduce by injecting their genetic material into a cell, and oftentimes they use RNA. With RNAi, one should be able to stop the RNA from viruses before it affects the cell. Earlier research concerning mice showed promise. Mice infected with hepatitis had fewer viral particles in their blood when treated with an RNAi drug.

But the drugs described by the New York Times, attempting to treat macular degeneration, did not work as expected. The RNAi didn't work by silencing genes, but instead helped to activate the immune system. One of the potential hallmarks of RNAi technology is its specificity: you can target a particular gene, and not have a system-wide affect. If it doesn't work by silencing genes, there are questions to what else it can do, especially whether or not it has harmful side effects.  

Even as we think we can unlock the mysteries of how the cell works, there are even more mysteries that arise when we try to use these ideas for ourselves. But regardless, new ideas and discoveries continue to be made, and one day, maybe, we'll understand how the cell functions completely and thoroughly.

Posted by katgor (2B)