Sir Alec Jeffreys said that the tool, which was meant to catch criminals who reoffend, has created a vast database of gene profiles of thousands of innocent citizens.

Professor Jeffreys, who is head of genetics research at Leicester University, said: “Now hundreds of thousands of entirely innocent people are populating that database, people who have come to the police’s attention, for example by being charged with a crime and subsequently released.”

Speaking as the Nuffield Council on Bioethics announced that it would carry out a public consultation on legislation on the storage of DNA material, he said: “The real concern I have in the UK is what I see as a sort of ‘mission creep’.”

He said that the samples were “skewed socioeconomically and ethnically”.

“My view is that that is discriminatory,” he said. He also raised concern that samples could be used for different purposes in the future.

The national DNA database, which was introduced more than ten years ago, is the largest in the world, with 3.6 million entries.

Since 2003 anyone arrested by police for “recordable” offences, ranging from murder to drink driving and vandalism, has their DNA taken.

In 2005-06 scientists made 45,000 DNA matches for crimes including 422 murders, 645 rapes, 256 other sex offences, 1,974 other violent crimes and more than 9,000 domestic burglary offences.

In January a report by the Home Office showed that the database included 139,463 people who had never been charged or cautioned over an offence.

The Home Office report showed that 5.24 per cent of the population has a DNA profile held on the database. This compares with an EU average of 1.13 per cent and 0.5 per cent in the US.

Last week the Prime Minister, during a visit to the Forensic Science Service, said that he had given his own DNA sample voluntarily in 1999 and that the maximum number of samples possible should be held on the database.

Sir Bob Hepple QC, chairman of the Nuffield Council and Emeritus Professor of Law at the University of Cambridge said: “We want to hear the public’s views on whether storing the DNA profiles of victims and suspects who are later not charged, or acquitted, is justified by the need to fight crime.”

He agreed with Professor Jeffreys that the database seemed skewed and said:

“Certain groups, such as young males and ethnic minorities, are over- represented on the database, and the council will be asking whether this potential for bias in law enforcement is acceptable.”

But Tony Lake, Chief Constable of Lincolnshire and a national police spokesman on the use of DNA, said that there were misunderstandings about the database. He said that it was not a conviction database but an intelligence tool.

He said that a large proportion of suspects who were arrested were not taken before the courts because there was a problem with evidence. Parliament had decided that the power to keep the material was proportionate to public safety.

But Mr Lake said that police accepted that there were public concerns about the DNA database and supported the decision by the Home Office to carry out a consultation on the creation of an independent regulator.

Defending the gathering of data, he said that matches from scenes of crimes against suspects who were not charged had later linked 3,000 to crimes, including 37 murders and 90 rapes.

GENE POOL

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