“The sci-fi vision of a molecular medical team that can be injected into a patient, coursing through his bloodstream to diagnose a disease and treat it, has taken a step nearer to reality” (AFP Discovery Channel).

On 28th April 2004, Ehud Shapiro and colleagues, from the Weizmann Institute, reported online in Nature the creation of the first molecular computer that could have medical use. This computer exploits the base-pairing properties of DNA to detect mRNAs that are diagnostic for disease and then destroys them by releasing antisense DNA molecules. The computer is “so small that about a trillion can fit in a drop of water” (The Telegraph) and “is listed in the 2004 Guinness Book of World Records as the world's smallest biological computing device” (The Guardian).

“The computer has two states, 'yes' and 'no', and changes from one to the other on the basis of a single variable, like the presence or absence of the RNA it is looking for. If at the end of a series of steps it is in the 'yes' state, the diagnosis is positive” (The New York Times).

What do the experts think? '“I think it's very elegant — almost like a beautiful mathematical proof”, said George Church. “But it's not working in human cells yet”' (The New York Times).

The molecular computer proved its worth in the optimal conditions of the laboratory, but “to actually track down and disable cancer cells in a human body, it would have to survive the hurly-burly of proteins, lipids, polysaccharides and nucleic acids, any of which could block or disable it” (The Guardian). But, Professor Shapiro is upbeat: '“Only two years ago we predicted that it would take another 10 years to reach the point we have reached today”' (The Guardian).