This week in BioNews, I report on a drug that can ‘silence’ disease genes.
For those who haven’t heard of BioNews, it’s a news digest and commentary focussing on genetics, assisted conception, embryo and stem cell research, among other areas. Read it. I write for them every now and again.
Researching this article, I got to delve into the slightly bonkers but bleeding-edge world of RNA interference, known in science circles as RNAi. Despite the discoverers of RNAi – one of whom is called Professor Fire (!) – winning a Nobel Prize in 2006 I’d never heard of it before. I think I was in a pub at the time.
The biological process amazes me (which is why I haven’t just said ‘read my article, please’ and left it at that). It’s a whirling dervish of tiny strings of genetic words and proteins with names like dicer, argonaute and peewee (OK, actually PIWI). But what is it?
In essence, RNAi is a way to switch genes off. Biologist Christine Vogel wrote:
“If our cells were little kitchens, then the DNA would be the cookbook with all the recipes, RNAs the transcripts made from the book, and proteins the final meals that are made.”
RNAi happens between the transcript and the meal. It stops the meal from being served, perhaps like a molecular Basil Fawlty discovering a rat in the kitchen.
By stopping proteins from popping out, RNAi also stops your genome from reshuffling and protects against viruses and other ‘foreign genetic material’. Once, I took a genetics module. Our lecturer was fond of telling us that when you touch another DNA-containing organism – like when you shake hands or something more intimate – strands of their DNA can get into your cells. This, I guess, is how your body stops your mate’s genes from causing problems inside you. (I thought about tempering the euphemism, but where’s the fun in that?)
All this means your genome contains ways to protect itself. To me, that’s amazing. Now biotech firms are pursuing ways of harnessing RNAi to treat some causes of blindness, Huntington’s disease, amyloidosis (which I talk about in the main article), viral infections and perhaps even cancer.
If you’re interested in learning more, the scientific powerhouse Nature produced a slideshow and animation, showing how RNAi works. (It’s quite jargony but, on the plus side, makes the whole process look like a sort of cute dystopian future in which we’re all slaves to giant globular overlords.)