Question: why is the transgenic mouse so important to you?

Ian Simpson answered on 22 Jun 2014:

It was a hugely complex experiment that ultimately took over 5 years to complete and was very important to the lab I was working with at the time. There were a lot of technical difficulties and it took a lot of blood, sweat and tears to get it working. So there was certainly a personal aspect to the achievement, but it has allowed that lab to now take their research on to the next level in terms of manipulating the expression of the gene that they’re interested in studying in the mammalian brain.

This particular mouse was special because unlike the majority of transgenic mice it is not a straight “knock-out” of the gene. Most transgenic mice aim to destroy the function of one gene for good. So all mice in that line have the mutant gene and you can compare those animals to unaffected mice and learn things about what the gene does. However, for many genes (including the one we worked on) the effect of knocking the gene out is catastrophic and you don’t learn much beyond the major things the gene is required for. In the mouse I made the gene wasn’t destroyed, but marked for deletion using a special technique called Cre/loxP technology. This means that we could delete the gene when and where we wanted which allowed us to tease apart much more subtle functions of the gene in the development and function of the brain. The mouse line is still being widely used by my old lab (and indeed in other labs around the world) and they’re publishing some wonderful research using it which is very pleasing.