The genetic records, which are often taken without parental consent and from children who have never committed an offence, are stored permanently on police files.
Critics fear the real number of under 16s on the system could be even higher as Government figures show the current age of the individual, rather than their age when they were added.
The controversial database – already the world’s largest – holds information on more than 4.5 million people around the UK. Covering 7.5 per cent of the entire population, it is said to be increasing by 150 new entries every hour.
Liberal Democrat Shadow Home Secretary Nick Clegg said the figures underline the “shocking extent” to which the database has intruded into the lives of our children.
“Thousands of these children will have been found guilty of no crime, yet samples of their DNA will remain on file for life,” he said.
“The disturbing and illiberal policy of adding a child’s most personal information to a massive government computer system, simply on the grounds of an accusation, must stop immediately.”
Under rules introduced in 2004, police are able to take swabs from anyone they arrest. Whether or not the person is eventually convicted, the information is stored until they die.
People can write to chief constables, asking for entries to be deleted but this will only work if they can prove they are an “exceptional case”.
The Home Office says there is nothing to fear from the system, describing it as a useful crime-fighting tool. About 3000 people are matched to crime scenes using the database every month.
The department’s website claims, “Any intrusion on personal privacy is proportionate to the benefits that are gained.”
However, campaigners think it is counter-productive to hold the details of innocent people who may not commit a crime in the future.
Shami Chakrabarti, director of civil rights group Liberty, told the Daily Mail the DNA database has become “a national disgrace, stuffed with innocent children and a disproportionate number of black people”.
She said, “It is time it was limited to those who are guilty or under investigation for sexual or violent crime.”
Earlier this year it emerged that 50 children under 10 are stored on the database – including a seven-month-old baby. However, police do not have powers to take DNA from anyone under the age of 10 without the consent of a parent or guardian.