] By raiding nature's tool cabinet, researchers have ] developed a potentially faster and more practical version ] of the polymerase chain reaction (PCR), itself a ] foundation of modern genetics. ] ] The breakthrough, called helicase-dependent amplification ] (HDA), could result in small, hand-held devices which ] enable doctors to test blood samples directly in the ] surgery and forensic teams to detect a suspect's DNA at a ] crime scene. I am going to go ahead and file this one under "Damnit, why didn't I think of that". This is a discovery that someone could have made ~25 years ago. Helicases were discovered in 1976, and Mullis presented PCR to the world in the early 80s. If Kary had of thought about adding helicases to his tube of nucleotides and polymerase, it would have saved alot of work for grad students in the 80s (of course, just the fact that he came up with PCR already saved grad students from alot of work, but whose counting). PCR sans helicases require temperature changes in a cyclic fashion in order to make the copies of the DNA. Before the invention of the thermal cycler (god bless this machine), grad students would have to move tubes from water bath to water bath by hand (keep in mind that to make enough copies to work with, the PCR reaction has to be cycled through all required temps ~25-30 times, which resulted in hours of moving tubes every couple of minutes to a different water bath (once again, god bless the thermal cycler). Adding helicases to the mix was a genious idea - could be nobel worthy. With helicases, the reaction can take place at 37 degrees, which means that PCR just got portable, and cheaper too (helpful for labs without alot of money to buy a thermal cycler). My hats off to these scientists....its always those discoveries that were sitting right in front of our faces for years that are sometimes the most amazing. [cool -k] New Scientist |