Scientists have created the first device which allows people to turn genes in mice on and off at will using only their brainwaves.

In humans, the ability to regulate the expression of genes through thoughts alone could open up an entirely new avenue for medicine. A monitoring system that could pick up early neurological signs of an impending epileptic fit or a migraine, for example, could automatically trigger the manufacture and release of protein-based medication within the body.

“Being able to control gene expression via the power of thought is a dream that we’ve been chasing for over a decade,” said Dr Martin Fussenegger from ETH Zurich, who led the research.

The study made use of a human gene implanted in mice. A tiny chamber containing human cells and an LED light was inserted under each mouse’s skin. The genes had been genetically modified to be sensitive to light, which made it possible to trigger and manage their protein production through shining the near-infrared light from the LED on them.

The human test subjects were divided into three groups, and asked to either meditate, play a game of Minecraft, or watch the light coming from the mouse’s body. Their brain activity was captured by a headset and analysed to establish their state of mind. The resulting signal was transmitted to the mice in the form of an electromagnetic field, which was able to light up the LED.

The quantity of protein created by the guest genes depended on whether the human wearing the headset was relaxing or concentrating on playing Minecraft.

Those who were asked to keep their eye on the mouse were able to see the effect their brain activity had on the red-coloured light, and thus on the genes within the implant. After some practice, this group learnt to exert conscious control over the amount of protein produced. They were able to alter their state of mind in order to change the output of the genes; a finding which gives the researchers hope that similar techniques could be used to influence implants within a person's own body.