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Digital DNA Circuits
TheSync writes "ScienceNews has a story about digital DNA circuits. The circuits use proteins that activate or deactivate genes on the DNA for control. Since an inverter and an AND gate have been created, any digital logic circuit can now be done in DNA. Moreover, evolution can help make circuit elements work better. There is even a "databook" of BioBricks circuit elements and BioSPICE for biocircuit simulation."
And people have known about them only for, oh, a few decades.
But proteins go into a little 3D bag, while transistors need to be packed near a flat surface with current VLSI technologies.
He wanted to remind you that he has held the copyright for DNA for billions of years now..
He's been in contact with his lawyers and is tallying your bill as we speak.
Even your body doesn't rely upon chemical reactions to accurately predict certain outcomes. Studies have shown that nerve fibers in your arm will often send a "the ball is coming" signal to your brain well in advance of the actual signal reaching your fingers. This sort of predicative function makes complex tasks like walking and talking much easier, but when it catches up to you (like when you fall on the bottom step of a flight of stairs because you forgot how many steps there were) you crash and burn.
The point is, that chemical reactions are very slow. If they were faster, your brain (and your neurons in your arm) wouldn't have to guess. Because they're so slow they'd be very poor at brute force attacks, regardless of the sheer number of cells.
So, yes, you're dreaming.
Transcription and translation happen at about 45 nucleotides per second in bacteria, meaning it takes at least a few seconds to get a signal through a genetic "gate" or "switch".
... to play the game of life?
The most interesting thing about this announcement is that this guy has been able to use evolution to improve his circuits. I don't expect molecular computers to surpass electronic computers, at least right away -- although they could theoretically perform faster than electronic computers in the short term, any advantage is offset by the time needed to convert the information to human-readable form (by finding and correctly reading the DNA sequence). As the article says, it's better to take advantage of the fact that you can "work with" bacteria. But if DNA computers could repair and upgrade themselves, they would have an advantage that electronics currently does not have. Electronics already is under intense artifical selection, and it can reproduce itself after a fashion, but unlike copper and aluminum, DNA computers can be randomly mutated, and the close homology between computers ensures that some of those mutations will be beneficial.
YES
NO
MAYBE
Do not try to read the dupe, thats impossible. Instead, only try to realize the truth
What truth?
There is no dupe
Reports of this sort have been coming out for a few years now - basically, all they are doing is a controlled induction of a promoter. It's nothing amazing. Chaining one promoter to express another promoter ad infinitum (or to restrict expression) is already done in nature and used extensively to create transgenic cell lines, bacteria, etc. Hell, they've already developed means to do basic computations with DNA that are more applicable/advanced then this in some respects.
I was listening to NPR the other day which focused on DNA as a computer.
The guy interviewed correllated the DNA genetic map to spaghetti code, a programmers worst nightmare. Apparently all through the genetic make-up of our bodies are "fuction calls" (to put it simply) and pathways that reference other calls and other pathways, over and over upon itself for a hundred million lines.
Its not the listing of the GTAC code (ie, genetic map) that's really necessary. Though of course it plays a part. Its the understanding of such code, what it does and what it controls, where power lies.
The guys interviewed all guessed it would be a hundred years or more before we began truly understanding what "functions" do what in the DNA strand and how it affects the organism in question.
Food for thought.
Yes, but if you have several trillion copies of your program you can run them all in parellel. Think of cytography....you could make a bioprogram that's designed to find the 128 bit key. There's 2^128 possible solutions. So if you have a whole bunch of these 2^1000 bio-programs in a solution, you can quickly find the 128 bit key. Look here under DNA computing for an example of why this stuff is useful, even if it is slow compared to silicon.
In the course of her work with Watson and Crick, Rosalind Franklin had to do a serious amount math by hand (Patterson analysis to create Patterson maps). Later, after her work on DNA she was forced to hire a computer (an 18yr old girl) to do the leg work on the data she gathered on the Tobacco Mosaic Virus.
Today I read here http://www.sciencenews.org/20030426/bob11.asp (Computer circuits made of genes may soon program bacteria)
"Silicon circuits perform complex operations using a handful of simple components known as logic gates. Genetic- circuit engineers are now building the same devices inside cells."
I wonder, what she would have thought, to know that very thing she was studying could some day be used to do the math that took up so much of her time.