Question: what do you think the biggest breakthough in gene theropy in the last 20 years is and why you think so?

Louise Johnson answered on 22 Jun 2010:

Gene therapy as medicine is still at very early stages and there have only been a few cases where it has been used on humans. So I think in terms of treatments, there will be bigger breakthroughs in the next 20 years than in the last 20 years.

The coolest recent development in my opinion is the use of “RNA interference” – a way to switch genes off – which has been shown to work in adult mice. This is cool because, firstly, RNA interference has only recently been discovered in the first place – it’s amazing that we’re still finding out whole new ways in which genes can be controlled. Secondly, it’s likely that the reason RNA interference works is that it helps cells to protect themselves from transposons, and I always like to see a new way in which transposons are important!

Of course, a lot of the time you want to treat genetic disease by switching genes *on*, and RNA interference won’t be much use in those cases, but there are times when switching a gene off is useful – like you might want to stop a cancer cell from expressing the genes that say “feed me, human victim!”