Humans and all living organisms can be thought of as nature’s computers because essentially cells act as logic gates taking input from the world to process and respond to with certain metabolic processes. The goal of synthetic biology is to tap into these natural processes to build logic circuits.
Martin Fussenegger explains, “The human body itself is a large computer, its metabolism has drawn on the computing power of trillions of cells since time immemorial. And in contrast to a technical supercomputer, this large computer needs just a slice of bread for energy.”
The team was able to slot dual core processors into human cells after modifying CRISPR gene editing tools; normally these systems use guide RNA sequences to target specific DNA segments in the genome to make precise edites, but for this project a special version of the Cas9 enzyme was created that can act as a processor.
This newly created version of the enzyme reads guide RNA as inputs and expresses particular genes in response, which in turn creates certain proteins as the output. These processors act like digital half adders that can compare 2 inputs or add 2 binary numbers to deliver 2 outputs; to boost the computing power 2 processor cores were fitting into one cell.
These dual core cell computers could be stacked up by the billion to make powerful biocomputers for diagnosing and treating a variety of diseases and conditions; for example they could look for biomarkers and respond by creating different therapeutic molecules depending on whether one or other biomarkers were present.
“Imagine a microtissue with billions of cells, each equipped with its own dual-core processor. Such ‘computational organs’ could theoretically attain computing power that far outstrips that of a digital supercomputer – and using just a fraction of the energy.” says Fussenegger.
