Researchers on both US coasts have succeeded in accessing data stored in life's instruction set by using strands of DNA to mimic the operations of microprocessor circuitry.
The two separate projects illustrate the growing symbiosis between biology, computer science, and semiconductor manufacturing.
At California's Stanford University, graduate student Daniel Shoemaker and his colleagues have developed a chip that can tell scientists which of thousands of genes are "switched on" - or present in a cell - at any given time. From this information, researchers can understand how a cell, and subsequently an entire organism, changes when a gene is turned on.
By learning how cells react to the presence or absence of genes, scientists can better diagnose illnesses.
"It gives us for the first time a tool to simultaneously monitor how every gene changes," said Shoemaker, lead author of a December Nature Genetics paper on one application of the chip.
Shoemaker's work is based on the gene chip developed by Affymetrix, a Santa Clara, California-based biotechnology firm. The chip will be the basis of several instruments used by physicians and researchers in genetic research. Shoemaker said tools based on Stanford's chip will help speed up the effort to discover DNA sequences and cure disease.
Shoemaker said the invention's biggest impact will be felt in basic biological research. For now, the researchers have created a chip describing the genome of a common yeast, but Shoemaker said there could soon be chips describing the entire genomes of the fruit fly, the mouse, and eventually, the human.
Meanwhile, researchers at New York's University of Rochester have used a strand of DNA in a drop of water to successfully duplicate the binary logic operations of microcomputer chips. The operation is the first step in what Animesh Ray, professor of biology at the University of Rochester, hopes will become a DNA computer.
Based on the work of mathematician Leonard Adleman, who built the first DNA computer, Ray's research will result in a machine designed to perform the most complex computations. "It will not be a replacement for calculators or computers," said Ray, who is working jointly with computer scientist Mitsunori Ogihara.
"By putting DNA on a chip, you are limited to two dimensions of searching and calculations. They are linear," he said. "With [our DNA computer], the space is three-dimensional, and calculations are simultaneous."
While the DNA computer could be used to sequence DNA and work on the human genome project, Ray sees more immediate benefits from the study of cells and genes for the field of computer science. Complex problems such as cracking large encryption keys can take months for microcomputers to solve, but might be calculated in a matter of weeks or days with a DNA computer, Ray said.
So far, Ray's research has been able to duplicate two logic structures used for addition and multiplication. But he's now trying to create and test other calculations.
"The computer we've created is very crude; [DNA computing] is in its infancy," said Ray.
