SMUGGLERS and burglars could now be trapped by something as innocuous as a wood shaving. Forensic scientists have found a way to DNA fingerprint wood, and their discovery could help track illegally logged timber or place a suspect at a crime scene.

Forensic botany is increasingly helping to solve crimes where the trail has gone cold (New Scientist, 2 March, p 33). But genetic fingerprinting can't be used to pinpoint the origin of timber, because DNA breaks down so quickly after a tree is cut. Also, wood contains substances which inhibit PCR, the standard technique for amplifying specific sections of DNA for identification.

Now Rémy Petit and his team at the National Institute for Agricultural Research at Gazinet have overcome these problems by devising an ultra-sensitive amplification technique that can spot minute fragments of DNA. Their technique searches for genetic material from plastids—parts of the machinery within plant cells. ...