hal2000 Bill On Earth, for about 3 billion years, DNA has been the most common material from which the computer programs that direct the processes of life have been made. Genomes, the collections of genes that tell cells what to do, are nothing but computer programs, almost always made of DNA, and packaged in a bunch of proteins and a few other things. Now it seems we are on the verge of using DNA for "conventional" computer programs. Is HAL2000 about to become a reality? In the scientific journal "Nature" for 000113, there will be a paper describing experiments that are a giant leap forward in the quest to harness the vast potential of DNA to perform the same tasks that now require silicon and miniature electronic circuits. The experiments, by scientists at the Univ. of Wisconsin, USA, demonstrate that DNA computing can be simplified and scaled up to tackle complex problems. DNA computing is an emerging technology that seeks to capitalize on the enormous informational capacity of DNA, biological molecules that can store huge amounts of information and act as computer programs to direct processes inside cells by which life is able to continue. The Nature paper describes the development of novel surface chemistry that greatly simplifies the complex and repetitive steps previously used in rudimentary DNA computers. Importantly, it takes DNA out of the test tube and puts it on a solid surface, making the technology simpler, more accessible and more amenable to the development of larger DNA computers capable of tackling the kinds of complex problems that conventional computers now handle routinely. In the Wisconsin experiments, a set of DNA molecules were applied to a small glass plate overlaid with gold. In each experiment, the DNA was tailored so that all possible answers to a computationally difficult problem were included. By exposing the DNA molecules to certain enzymes (protein molecules that speed up specific types of chemical reactions), the DNA's with the wrong answers were weeded out, leaving only the DNA molecules with the right answers. The appeal of DNA computing lies in the fact that DNA molecules can store far more information than any existing conventional computer chip. It has been estimated that a gram of dried DNA can hold as much information as a trillion CDs. Moreover, in a biochemical reaction taking place in a tiny surface area, hundreds of trillions of DNA molecules can operate in concert, creating a parallel processing system that mimics the ability of the most powerful supercomputers today, including your brain. The chips that drive conventional computers represent information as a series of electrical impulses using ones and zeros. Mathematical formulas are used to manipulate that binary code to arrive at an answer. DNA's are basically strings of molecular units called "nucleotides." There are four different nucleotides in DNA's. DNA computing depends on information represented by the sequence of these nucleotides along a DNA molecule. Certain enzymes are capable of reading these sequences and copying or otherwise manipulating them in predictable ways, depending on what the sequences are. The code for DNA computing is not binary bits (each 0 or 1, "on" or "off") but quaternary "quadits" which can be 0, 1, 2 or 3 (or A, T, C or G to use the conventional symbols used by chemists for the four different nucleotides). A byte (8 bits) of a binary computer can have 256 different values. A byte of a quaternary DNA compuer can have 256 x 256 = 65,536 different values and can requires only about 1/10,000,000th the space needed for a binary byte on a computer chip. Conventional computing, with ever more and smaller features packed onto the silicon chips that control it, is approaching the limits of miniaturization. DNA computing is one potential way around that barrier. DNA computing technology is thought to be still far in the future, much like the powerful desktops that are common today were thought to be 25 years ago. The pessimists of desktop development are quiet these days, busy working at their desktops. Just remember, folks, HAL is not likely to be as gentle with doubters about his emergence as most desktops have been with the doubters of the 70's. Isn't that right, HAL? Copyright 2000 000112 ... Shar um, yeah. 000130 ... Astro Smurf Thta's right, David. 000131 ... Thyartshallshant Hal was FUCKIN COOL! Hell yea. "I can't do that, dave" HEHE, I love it! 010104 ... open the pod bay door Oh, and Dave, that's "HAL 9000," please try to remember that next time, if there is a next time. 010105 ... Tiffa Interesting thinking...hope you don't mind i am printing this for my AP Bio course. We have nothing else to do since we all took the clept. Thanx. 010611 ... j_blue that method of mass/specialized super computation was also duplicated using light cant remember the exact experiment, but the logic was identical had to have gotten to the article from cnn, nytimes, /., or plastic at present, the logic used to devise those experiments is not practical has anybody heard about the experiements that used living nerve cells (i think from leaches) to make small dynamic supercomputers? again, it isnt practical yet anyways 010611 what's it to you? who go blather from