Scientists in Israel have built a tiny biological computer that might be able to diagnose and treat certain types of cancer, says the journal Nature.
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, says the article in the latest issue of the journal.
Developed by a team from the Weizmann Institute of Science led by Dr Ehud Shapiro, 'the device only works in a test-tube and 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,' it said.
The device 'measures just 100 nanometres across, meaning that a thousand billion would fit into a teardrop and almost ten million on the full stop at the end of this sentence,' said the Times, London.
'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,' said the Nature article.
In other words, they could diagnose disease from within cells and dispense drugs as necessary.
"It is decades off, but future generations of DNA computers could function as doctors inside cells," Dr Shapiro is quoted as saying. Our medical computer might one day be administered as a drug, and be distributed throughout the body by the bloodstream to detect disease markers autonomously and independently in every cell.
"In this way, a single cancer cell could be detected and destroyed before the tumour develops. Even in a late-stage cancer, this kind of treatment could reach every secondary growth, however small, and effectively terminate the disease."