In a paper published in the journal "Science" on Friday, the team described their system of genetic transistors, which can be inserted into living cells and turned on and off if certain conditions are met. The researchers hope these transistors could eventually be built into microscopic living computers. Said computers would be able to accomplish tasks like telling if a certain toxin is present inside a cell, seeing how many times a cancerous cell has divided or determining precisely how an administered drug interacts with each individual cell.
Once the transistor determines the conditions are met, it could then be used to make the cell, and many other cells around it, do a specific thing--like telling cancerous cells to destroy themselves.
"We're going to be able to put computers into any living cell you want," lead researcher at the Stanford School of Engineering Drew Endy explained to the San Jose Mercury News. "We're not going to replace the silicon computers. We're not going to replace your phone or your laptop. But we're going to get computing working in places where silicon would never work."
The team demonstrated their work using E. Coli bacteria, an organism commonly used in genetic research.
Traditional computers use millions of tiny transistors, which control the flow of electrons in the form of the zeros and ones that make up binary code. Multiple transistors working together can form something called a "logic gate," which serves as the basic building block of all computations performed by computers the world over.
The researchers' biological transistors, which they've dubbed "transcriptors," use enzymes to control the flow of RNA proteins along a strand of DNA, just like a computer would use silicon transistors to control the flow of electrons.
In addition to changing the way people think about the human body, biological computers made using these transcriptors could be used to learn more about an litany of other living systems.
"For example, suppose we could partner with microbes and plants to record events, natural or otherwise, and convert this information into easily observed signals," Endy told the Independent. "That would greatly expand our ability to monitor the environment."
Extreme Tech reports:
You need more than just...[logic] gates to make a computer, though. You also need somewhere to store data (memory, RAM), and some way to connect all of the transcriptors and memory together (a bus). Fortunately, as we've covered a few times before, numerous research groups have successfully stored data in DNA--and Stanford has already developed an ingenious method of using the M13 virus to transmit strands of DNA between cells...In short, all of the building blocks of a biological computer are now in place.
This isn't to say that highly functional biological computers will arrive in short order, but we should certainly begin to see simple biological sensors that measure and record changes in a cellâ€™s environment. Stanford has contributed the...gate design to the public domain, which should allow other research institutes, such as Harvard's Wyss Institute, to also begin work on the first biological computer.
The researchers have published some of their findings under a public domain license, in the hopes that other scientists will more easily be able to build off their discoveries.
Check out this video of Endy explaining how transcriptor logic gates function: