Sheila Willis, director of the State Forensic Laboratory which will operate the database for the gardai, defended the initiative in the face of strong criticism from rights activists.

The president of the Irish Human Rights Commission (IHRC), Maurice Manning, recently said the database proposed by justice minister Brian Lenihan had "far-reaching implications for human rights".

"A DNA database stores and retains the most personal information an individual may possess.

The guarantee of a person's right to privacy is fundamentally affected by the retention and storage of their DNA on a database, " he said.

But Willis told the Sunday Tribune the only personal information revealed by the so-called 'junk DNA' used in crime detection was whether the person was male or female.

"It will not indicate the presence of any diseases, physical attributes or any such personal information. What it will do . . . assuming the full 10 tests are done on a DNA sample . . . is tell the gardai that there is a one in 10 billion chance that DNA is shared by another person, " she said.

"DNA is an investigative tool which helps the gardai solve crime but it does not of itself accuse anybody. Information or intelligence is far less reliable than verifiable scientific evidence."

The IHRC had also voiced concern that the DNA of crime suspects would be held indefinitely even if they were not charged, and said such samples should be removed and destroyed if the person was not charged. While reluctant to become involved in the debate about the extent of DNA sampling, Willis said: "The more DNA profiles on the database of those who are likely to commit a crime, the better it will be as a tool to fight crime."

In the UK, 4.5% of the population, or close to three million people, are on the database . . . a percentage considered the best to maximise the effectiveness of a database in fighting crime. Willis said Ireland's forensic laboratory currently had DNA samples taken from around 500 cases.

"This is only the tip of the iceberg and we need more to make the database work, " she said. "We are behind most of Europe in the establishment of a DNA database and I am looking forward to the Criminal Justice [Forensic Sampling and Evidence] Bill being passed by the Dail."

Brian Lenihan has already said he will press ahead with plans to set up the database despite the IHRC's concerns on human rights.

Meanwhile, plans by the justice department to build a new state-of-the-art forensic laboratory on its current site in the garda headquarters in the Phoenix Park are likely to be delayed. The "cost effectiveness" of building the new lab is "currently being evaluated", a justice spokeswomen told the Sunday Tribune.

She added that Lenihan was also evaluating the findings of a major review of the resource needs of the forensic laboratory. The review was ordered by former justice minister Michael McDowell last December and was headed up by the former director of the Swedish state forensic laboratory Invar Kopp.

No details of Kopp's review were released by the department, which said Lenihan would "consider the next steps over the coming months".