SSS 2011-10-07

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To give researchers more genetic⁴ material to work with, a PCR instrument repeatedly heats and cools an original biological sample. Which gives enzymes⁵ a chance to replicate⁶ the DNA millions of times so it can be more easily analyzed⁷.

 

Such sequence amplification would be a boon⁸ to diagnosis in a doctor's office—especially when an infectious disease is spreading rapidly. Unfortunately, genetic tests usually take a day or two to complete. But researchers at the Lawrence Livermore National Laboratory aimed to speed up the process.

 

First they created an extremely fast thermal⁹ cycle, in which a sample experiences 45 degrees Celsius¹⁰ temperature changes per second. Then they searched for DNA amplification enzymes that could operate at that thermal cycling speed. And they found two that worked without any tweaking. The technique accomplishes a billion-fold amplification in well under three minutes. The work is in the journal Analyst¹¹. 

 

The system could make it possible to identify food contamination virtually instantly. Or an infection before you even finish coughing.

 

Thanks for the minute. For Scientific American's 60-Second Science, I'm Cynthia Graber.

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