Human thoughts can be used to turn on genes in mice, new research suggests.
A tiny, light-based machine uses people's brain waves to generate a flicker of light, which then turns on genes in the brains of mice. The new method could one day be used by people who suffer from chronic pain or epilepsy to instantly deliver drugs from a brain implant when they experience characteristic brain waves at the onset of pain or a seizure, said study author Martin Fussenegger, a researcher at the ETH Zurich in Switzerland.
"For the first time, it was possible to use brain waves — the subject's thoughts — to induce gene expression," Fussenegger told Live Science. [Biomimicry: 7 Clever Designs Inspired by Nature]
In recent years, scientists have developed tiny, biologically based machines from some of the fundamental building blocks of life, such as DNA, RNA and proteins. For instance, scientists have designed microbial drug factories out of yeast and bacteria that produce drugs like morphine. Other groups have created life-forms with completely man-made six-letter DNA. And still others have created tiny computer hard-drives that use DNA as the coding language.
Other researchers have designed cybernetic brain implants where, humans or monkeys can control the brain waves of monkeys. But few researchers have tried to combine both synthetic molecular machines and brain implants.
In their new study, Fussenegger and his colleagues asked several volunteers to meditate, concentrate by playing a game of "Minecraft" or control their brain activity with biofeedback, a technique where people sync their brain waves using a guided display Each of these activities produces a unique signature of electrical brain activity, which was captured by electroencephalography (EEG) and fed wirelessly into an implant in a mouse's brain.
"These brain-wave patterns they are recorded, processed and then we designated a certain threshold," Fussenegger said. "If the pattern goes above this threshold level, it turns on a near-infrared LED for a defined period of time."
This near-infrared light then trips a tiny cellular machine — a bacterial protein that is activated by light — inside the mouse's brain implant. The bacterial protein sets off a chemical cascade that turns on a tailor-made gene snippet that encodes a specific human protein. The team then verifies that the genes are activated by measuring the human protein levels in the mouse's bloodstream, Fussenegger said.
Tiny brain factories
Though the current experiment used a human protein with no therapeutic purpose, the same technique could eventually be used in the human brain to deliver precise quantities of drugs as needed, Fussenegger said.
For instance, just before an epileptic seizure, the brain produces a unique type of electrical activity that could trigger a tiny, light-activated genetic implant that quickly produces an anti-seizure medication. Chronic pain may also produce signature brain waves just before the onset of discomfort, which could be used to preemptively produce painkillers in the brain.
"This is an interesting proof of concept," said Kevin Gardner, a structural biologist at the City University of New York's Advanced Science Research Center who was not involved in the study.
But applications in humans are likely a long way off, Gardner told Live Science.
The study was published today (Nov. 11) in the journal Nature Communications.