Largest DNA-Based Computational Circuit Created

angry tapir writes "Researchers from the California Institute of Technology have built [abstract] what they claim is the world's largest computational circuit based on DNA (deoxyribonucleic acid), using a technology that they said could easily scale to even greater complexity." Adds reader cwmike: "The researchers formed 130 different synthetic DNA strands that can be used to compose logic circuits. From this source material, they created one 74-molecule, four-bit circuit that can compute the square root of any number up to 15 and round down the resulting answer to the nearest integer. In their setup, the multi-layered strands of DNA are fashioned (see video) into biochemical logic gates that can perform the basic Boolean AND, OR and NOR operations executed by today's transistor-based computer processors."

Comments

In their dreams!

[NoNonAlphaCharsHere]

I've been running a MUCH larger DNA-based computational circuit for YEARS now! Course, sometimes it fails me completely.

Re:In their dreams!

[Fluffeh]

Well, yes, while DNA based computing may sound like something from Science fiction, it looks like this is a small step:

The researchers formed 130 different synthetic DNA strands that can be used to compose logic circuits. From this source material, they created one 74-molecule, four-bit circuit that can compute the square root of any number up to 15 and round down the resulting answer to the nearest integer.

then

Reif also pointed out a few downsides. One is the speed of calculation. The execution of a single gate can take anywhere from 30 to 60 minutes. Executing a four-bit square root could take up to 10 hours.

So don't be expecting any DNA based mass computing revolution anytime soon.

Re:In their dreams!

[SanityInAnarchy]

If you're talking about your brain, that's not what this is. This is using actual DNA to perform computations.

Oh, by the way, last I checked, it's slow, and this is no exception:

Reif also pointed out a few downsides. One is the speed of calculation. The execution of a single gate can take anywhere from 30 to 60 minutes. Executing a four-bit square root could take up to 10 hours.

This isn't like quantum computing -- maybe they can make it faster, but I really don't see this having any inherent advantages over old-school tech like CMOS anytime soon.

What makes this interesting is the potential to do calculations inside living systems, or to actually interface our code with otherwise strictly biological processes. These "circuits" are just solutions of custom-designed DNA, and each "gate" takes small single-strands of DNA as input, and produce them as output, whether as a "wire" to another gate, or as the final output to be measured to check if the circuit is working. Now imagine putting that in a cell. (Oh, and this is why formal methods matter -- if someone's going to be putting code in your body, it's not enough to debug it, you want that shit proven correct.)

Disclaimer: While I did take a class (COM S 433 at ISU) which attempted to examine this stuff, this was covered at the very end of the semester, and no one (including the instructors) really had a good idea how these things actually work. I know enough to be dangerous, but there's a good chance I'm wrong about pretty much anything I say here. Read the papers yourself -- it's fascinating stuff.

Science: it's a tough life

[Walt Dismal]

I keep telling girls at bars I'm a scientist who just wants to perform a complex calculation using DNA and then they throw a drink in my face for some reason.