This is actually about scientific medicine and how it becomes progressively
better at treating cancer.
http://www.newsday.com/news/health/wire/sns-ap-molecular-computer,0,396724
8,print.story?coll=sns-ap-health-headlines
DNA 'Computer' Able to Detect Cancer
By CHRIS KAHN
Associated Press Writer
April 28, 2004, 1:29 PM EDT
Researchers have developed a vanishingly tiny "computer" that could someday
enable doctors to treat cancer and other diseases from inside the body.
The molecular-scale device, which is essentially a liquid mixture of synthetic
DNA and enzymes, is designed to sniff out chemical signs of disease and pump
out drugs in response.
In a new study, researchers say it showed promising results in a test tube.
Ehud Shapiro of Israel's Weizmann Institute of Science, who led the team of
computer experts and biochemists that built it, said the next step will be to
package the computer so it works within the complex chemical soup of the body.
"The problems are big, and we do not have a clear way to solve them," said
Shapiro, who describes the device in the study, published online Wednesday by
the journal Nature.
Molecular computers have only been around for a decade. Instead of micro chips
and processors, they harness the software-like ability of DNA strands to store
information. Enzymes "read" chemical sequences on the DNA in a way that allows
the computer to perform calculations.
Experts say such computers could become extremely powerful, given DNA's
potential to store huge amounts of information. The computing power of 1
trillion compact discs could be stored in less than an ounce of dried DNA.
John Reif, a computer science professor at Duke University who built his own
molecular computer in 2000, said until now no molecular computer has ever
demonstrated much practical use.
"It's really an ingenious concept," Reif said of Shapiro's computer. "This
could have a major significance in the medical world, if only they could get it
in the cell."
In the future, a doctor might inject trillions of the devices into a patient.
The computer is designed to detect cancer by monitoring concentrations of
certain molecules. If cancer is detected, the computer releases other molecules
that interfere with a cancer cell's activities and cause it to self-destruct.
Unlike many of its predecessors, the computer is autonomous -- it doesn't need
supervision or added chemicals to make it work.
Shapiro, who received a U.S. patent for a previous version in 2001, said the
new computer worked fine detecting chemical markers of lung and prostate cancer
in lab experiments using a pristine water solution.
But it could get confused if it were put in a medium teeming with other
molecules, Shapiro said. "There could be many reactions with many other
molecules that may be detrimental to either the computer or to the cell in
which it operates."