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. PCR enables detection of tiny traces of DNA through a reaction which creates multiple copies of a single strand of target DNA until enough is available to show up in a detector. As well as revolutionising crime forensics, PCR is now used routinely in hospitals to diagnose disease, in paternity cases that rely on genetic fingerprinting, in archaeology, and in all branches of biological and genetics research.
