Within a decade, forensic scientists will be able to produce a full genetic "photofit" of a suspect's weight, height, facial characteristics, hair and eye colour from a single cell or a drop of blood.
The Police Superintendents' Association annual conference in Bristol heard that forensic scientists are already developing techniques to extract DNA samples from wraps - the bags used to package and sell drugs.
They can analyse DNA contained in dead skin cells, saliva or faeces. In a recent case scientists successfully linked a package of drugs to a smuggler who had hidden it in his anus.
Within a year, scientists believe they will be able to obtain a DNA sample from a single flake of dandruff taken from a balaclava or motorcycle helmet, or from discarded clothes.
Kevin Sullivan, research and development manager at the Forensic Science Service (FSS), said that improved techniques should, in the next couple of years, enable the extraction of DNA from the surface of beer cans, cups or wine glasses by examining a single skin cell left on the hard surface.
This would be particularly useful in cases involving stolen vehicles or pub fights in which broken glass had been used to wound.
Detectives will be able to re-examine unsolved crimes, particularly murders and rapes. Stains and murder weapons could be retested. This could uncover vital evidence about suspects, as well as help to prove the innocence of people who have been unfairly convicted.
The National DNA database holds about 340,000 samples from known suspects and 37,500 samples taken from the scenes of unsolved crimes.
Dr Sullivan said that the FSS "genetic profile" might also reveal inherited defects, and the shape of the face, ears and nose: "That's the Holy Grail we are looking for," he added.
On the question of whether the National DNA Database should contain samples from every citizen rather than only from people arrested for imprisonable offences, as at present, Dr Sullivan said: "The technology is ready, the question is whether society is."
The cost of testing everyone in Britain and putting them on a database is estimated at pounds 1.5bn.
n Jack Straw, the Home Secretary, will today announce that he has brought forward a key election pledge to speed up the criminal justice system for persistent offenders. He will tell police officers that by 1 March next year, half of all repeat offenders should be dealt with within 71 days.Reuse content