New magic' DNA computer that grows as it computes

In a first, scientists have designed a new, super-fast form of a ‘magic’ computer made of DNA molecules that grows as it computes and can outperform all standard systems in solving important practical problems. Researchers from The University of Manchester in the UK showed the feasibility of engineering a universal Turing machine (UTM) – a computer that can be programmed to compute anything any other device can process. Electronic computers are a form of UTM, but no quantum UTM has yet been built.

The theoretical properties of such a computing machine, including its exponential boost in speed over electronic and quantum computers, have been well understood for many years – but the breakthrough demonstrates that it is actually possible to physically create a UTM using DNA molecules.

“Imagine a computer is searching a maze and comes to a choice point, one path leading left, the other right. Electronic computers need to choose which path to follow first,” said Ross D King, from The University of Manchester. “But our new computer doesn’t need to choose, for it can replicate itself and follow both paths at the same time, thus finding the answer faster,” said King.

“This ‘magical’ property is possible because the computer’s processors are made of DNA rather than silicon chips. All electronic computers have a fixed number of chips,” he said. “Our computer’s ability to grow as it computes makes it faster than any other form of computer, and enables the solution of many computational problems previously considered impossible,” he added.

“Quantum computers are an exciting other form of computer, and they can also follow both paths in a maze, but only if the maze has certain symmetries, which greatly limits their use,” King said. “As DNA molecules are very small a desktop computer could potentially utilise more processors than all the electronic computers in the world combined – and therefore outperform the world’s current fastest supercomputer, while consuming a tiny fraction of its energy,” he said.

DNA computing is the performing of computations using biological molecules rather than traditional silicon chips. In DNA computing, information is represented using the four-character genetic alphabet – A (adenine), G (guanine), C (cytosine) and T (thymine) – rather than the binary alphabet, which is a series of 1s and 0s used by traditional computers. The research appears in the Journal of the Royal Society Interface.