DNA computation gets logical

Aug 03, 2009

Biomolecular computers, made of DNA and other biological molecules, only exist today in a few specialized labs, remote from the regular computer user. Nonetheless, Tom Ran and Shai Kaplan, research students in the lab of Prof. Ehud Shapiro of the Weizmann Institute's Biological Chemistry, and Computer Science and Applied Mathematics Departments have found a way to make these microscopic computing devices 'user friendly,' even while performing complex computations and answering complicated queries.

Shapiro and his team at Weizmann introduced the first autonomous programmable DNA computing device in 2001. So small that a trillion fit in a drop of water, that device was able to perform such simple calculations as checking a list of 0s and 1s to determine if there was an even number of 1s. A newer version of the device, created in 2004, detected cancer in a test tube and released a molecule to destroy it. Besides the tantalizing possibility that such biology-based devices could one day be injected into the body - a sort of 'doctor in a cell' locating disease and preventing its spread - biomolecular computers could conceivably perform millions of calculations in parallel.

Now, Shapiro and his team, in a paper published online today in , have devised an advanced program for biomolecular computers that enables them to 'think' logically. The train of deduction used by this futuristic device is remarkably familiar. It was first proposed by Aristotle over 2000 years ago as a simple if…then proposition: 'All men are mortal. Socrates is a man. Therefore, Socrates is mortal.' When fed a rule (All men are mortal) and a fact (Socrates is a man), the computer answered the question 'Is Socrates Mortal?' correctly. The team went on to set up more complicated queries involving multiple rules and facts, and the DNA computing devices were able to deduce the correct answers every time.

At the same time, the team created a compiler - a program for bridging between a high-level computer programming language and DNA computing code. Upon compiling, the query could be typed in something like this: Mortal(Socrates)?. To compute the answer, various strands of DNA representing the rules, facts and queries were assembled by a robotic system and searched for a fit in a hierarchical process. The answer was encoded in a flash of green light: Some of the strands had a biological version of a flashlight signal - they were equipped with a naturally glowing fluorescent molecule bound to a second protein which keeps the light covered. A specialized enzyme, attracted to the site of the correct answer, removed the 'cover' and let the light shine. The tiny water drops containing the biomolecular data-bases were able to answer very intricate queries, and they lit up in a combination of colors representing the complex answers.

Source: Weizmann Institute of Science (news : web)

Explore further: Gold nanorods target cancer cells

add to favorites email to friend print save as pdf

Related Stories

Scientists build a better DNA molecule

May 27, 2008

Building faultless objects from faulty components may seem like alchemy. Yet scientists from the Weizmann Institute’s Computer Science and Applied Mathematics, and Biological Chemistry Departments have achieved just that, ...

Repeating genes

Nov 26, 2007

Huntington’s disease is a genetic time bomb: Programmed in the genes, it appears at a predictable age in adulthood, causing a progressive decline in mental and neurological function and finally death. There is, to date, ...

ASU professor to explore DNA based computing

Oct 19, 2005

Arizona State University School of Life Sciences professor Wayne Frasch was recently awarded a $1.2 million grant from the Defense Advanced Research Projects Agency and the U.S. Air Force Office of Science Research to fund ...

Researchers aim to use DNA molecules to create computers

Mar 11, 2005

Instead of waiting weeks for computers to grind out solutions to complex problems, scientists may someday get answers instantly thanks to a new type of "oracle" computer that will have all the answers built in, predict Duke ...

Scientists develop molecular keypad lock

Jan 24, 2007

Keypad locks, such as those for preventing auto theft, allow an action to take place only when the right password is entered: a series of numbers punched in a pre-set sequence. Now, a team of scientists at the Weizmann Institute ...

Stopgap DNA repair needs a second step

May 04, 2009

One can have a dream, two can make that dream so real, goes a popular song. Now a Weizmann Institute study has revealed that it takes two to perform an essential form of DNA repair.

Recommended for you

Gold nanorods target cancer cells

Dec 18, 2014

Using tiny gold nanorods, researchers at Swinburne University of Technology have demonstrated a potential breakthrough in cancer therapy.

User comments : 5

Adjust slider to filter visible comments by rank

Display comments: newest first

thales
1 / 5 (1) Aug 03, 2009
What! That is pretty frickin' sweet.
Damon_Hastings
not rated yet Aug 03, 2009
Dude, that just blew my mind...

I wonder what the theoretical computing capacity would be for an entire kilogram of molecular computers?

Next up: molecular-sized *quantum* computers. We're going to need longer encryption keys...
NeilFarbstein
1 / 5 (2) Aug 04, 2009
wow
NeilFarbstein
1 / 5 (3) Aug 05, 2009
amazing. I'm gonna read the paper. I invented a method of synthesizing DNA oligos that will be useful if this type of computation gets bigger and more important. I had an R&D contract with a pharmaceutical company to develop it. We are now released from that contract. Prospective partners should contact me at protn7@att.net
N_O_M
2.3 / 5 (3) Aug 05, 2009
I invented a method of synthesizing DNA oligos
Yeah, like you have claimed to invent everything. Probably including the wheel.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.