Could nanomachines be tomorrows doctors?
Scientists have built a tiny biological computer that might be able to diagnose and treat certain types of cancer. The device, which only works in a test-tube, is years from clinical application. But researchers hope it will be the precursor of future ‘smart drugs’ that roam the body, fixing disease on the spot. Instead of silicon chips and electrical circuits, the miniscule machine is made of DNA. And rather than being controlled by electrical signals, it senses changes in its environment and responds by releasing biological molecules. The biocomputer senses messenger RNA, the DNA-like molecule that helps create proteins from the information in genes. In particular, it can detect the abnormal messenger RNAs produced by genes involved in certain types of lung and prostate cancer. When the computer senses one of these RNAs it releases an anticancer drug, also made of DNA, which damps expression of the tumour-related gene, researchers report in Nature1. Billions of the computers can be p
