The scientist who pioneered genetic fingerprinting says he's concerned that the personal data of innocent people is being wrongly held by police.
The DNA samples of the guilty and innocent are kept on the database
Professor Sir Alec Jeffreys told the BBC the retention of thousands of innocent people's DNA raised "significant ethical and social issues".
He was speaking as the government launched an inquiry into the way the national DNA database is used.
Per capita, it is the world's largest database and holds the DNA profiles of 4.5m people. The equivalent system in the US, known as CODIS, and run by the FBI, contains over five million DNA profiles.
When first launched in 1995, only the DNA of convicted criminals were kept by police. But following a change in the law in 2001, all DNA collected by forensics - for whatever purpose - can be stored permanently.
Innocent and guilty on database
That ranges from people who voluntarily give police a DNA swab in order to eliminate themselves from investigations - to convicted rapists and murderers.
Since 2004, the data of everyone arrested for a recordable offence in England and Wales - all but the most minor offences - has remained on the system regardless of their age, the seriousness of their alleged offence, and whether or not they were prosecuted.
Such is the controversy surrounding the database that last September one of England's most senior appeal court judges, Lord Justice Sedley, called for the database to be made compulsory for all UK residents as well as visitors to Britain.
At the time he said the current system was "indefensible".
His call has been echoed by the law reform group Justice, which described the consultation as a "public relations gimmick".
Deoxyribonucleic acid (DNA) is found in virtually all cells
Only a tiny sample of saliva, blood, semen, etc, is needed for testing
At the molecule's core is a long sequence of chemical units, which is checked for a gender and 10 other 'markers'
Probability of a chance match is less than one in one billion
A match may be with a specific individual or hint at a relative
Profiles can provide indications of ethnic origin
They do not point to genetic disorders or susceptibilities
Justice's Director, Roger Smith, said: "The national DNA database should either list those guilty of a crime or everybody in the country.
"At the moment, it contains the DNA of criminals and a whole number of other people who have attracted the interest of police officers but never been convicted - in many cases, never even charged - with a crime."
Recently, Home Office Minister Tony McNulty said the database had helped police solve as many as 20,000 crimes a year.
But according to the government's own figures, the database contains the genetics of a disproportionate number of ethnic minorities.
Forty per cent of black men in the UK have their DNA stored on the database and there are concerns that it could be open to abuse.
The president of the National Black Police Association, Chief Superintendent Ali Dizaei, said, "Black men are disproportionately targeted right across the criminal justice system where there is no evidence whatsoever that they disproportionately commit crime.
"We see the current data as a classic example of institutional racism."
Professor Sir Bob Hepple, who until December was Chair of the Nuffield Council on Bioethics, said: "Young black males are over-represented on the National DNA Database. This may have arisen from policing practices and the disproportionate arrest of certain ethnic groups."
But he said: "The establishment of a population-wide forensic DNA database cannot be justified at the current time. The potential benefits would not be great enough to justify the cost and intrusion to privacy."
Geneticist Sir Alec Jeffreys first found a way to identify people through their DNA by accident at the University of Leicester two decades ago.
He said he welcomed an inquiry into public attitudes to the database and how it is developing.
"The national DNA database is a very powerful tool in the fight against crime," he said.
"But recent developments such as the retention of innocent people's DNA raises significant ethical and social issues."
Balancing rights and safety
The government consultation will be conducted by the Human Genetics Commission advisory body.
Over the next six weeks, it will hold sessions with dozens of members of the public in an exercise costing £75,000.
The conclusions will be fed back to the government in a report next year on the forensic use of DNA.
The man in charge of the inquiry Human Genetics Commission chairman Sir John Sulston said: "There is an important balance to be struck between individual rights and public safety and we need to know how people feel about these issues".