Ireland's DNA Database System has grown by 20% and contains 58,703 DNA profiles, a new report has found.

It comes as 920 crime investigations, including robberies, firearms offences, serious sexual assaults, aggravated burglaries and other crimes, were assisted by the database.

The database, which is populated by samples taken from crime suspects, people convicted of serious crime and crime scenes, is used for the investigation and prosecution of serious crime.

The 2021 DNA Database System Oversight Committee's annual report, which was exclusively seen by RTÉs Morning Ireland, shows there were 58,703 profiles in the database at the end of 2021.

The figure consists of 43,471 profiles on a reference index, a category in the data base that includes known suspects, convicted offenders and people volunteering specimens.

The number of profiles in the reference index increased by 7,275 from 36,196 in 2020.

There are 4,559 profiles on the Elimination Index, a category within the database that includes gardaí, Forensic Science Ireland (FSI) staff and An Garda Síochána Ombudsman Commission (GSOC).

The index is used to eliminate contamination of samples from crime scenes.

There are 946 profiles on the Identification Index, a category that includes profiles from missing persons, their relatives, and unidentified human remains.

When profiles are added to the database two potential matches or hits can occur.

A crime stain can match another crime stain, suggesting a link between crimes; or the crime stain can match to a person suggesting a link between the person and the crime.

In this context, in 2021 the database had 759 hits and assisted in 920 investigations.

A hit is where the DNA database connects a crime stain, a crime scene sample, to a suspect. It is a match to other information that exists on the database at that time.

The database also saw a 16.7% increase in the number of crimes stains, which are samples collected at crime scenes.

The crime-solving capacity of the database continues to grow and Forensic Science Ireland (FSI) estimates the number of profiles on it has reached 60,000 since the report was completed.

It said 48 out of every 100 crime scene samples will be linked to a person.

From the Irish database, there were 871 international matches in 2021, with the largest number of these in the UK. The committee's annual report said findings to date highlight the value of the DNA Database System to fighting crime.

'Powerful intelligence tool'

FSI Director General of FSI Chris Enright said "over 5,000 investigations that have been supported by the DNA database since its inception" in 2015.

"Forensic Science Ireland has a responsibility for managing the National DNA database, which has grown more and more as a powerful intelligence tool over the last number of years.

"Since the database was launched we have assisted in over 5,000 investigations. There were 759 hits in 2021 alone, which assisted in 920 cases," said Mr Enright.

"At present, we have over 60,000 profiles on the database. There is a huge amount of very valuable information and that comes with the responsibility on us to make sure that it is managed appropriately, all the way from the processing of samples to the processing of data," said Mr Enright.

"What has increased 20% year over year is the total number of reference profiles that are on the national database. There have also been an increase in the number of crime stains that are recorded on the database.

"The database has been growing year-on-year, so there is nothing specifically unusual about that level of growth. It really has being growing significantly year-on-year since it was introduced in 2015. A big factor is the knowledge that from an investigative point of view that this is a very powerful tool.

"Gathering DNA samples from crime scenes and gathering reference profiles from suspects can really assist in the investigative process. That is acknowledged and led to the growth in services over the course of the year," said Mr Enright.

"There is a very broad range of investigations that the DNA database has supported. A large number of burglaries, robberies, thefts, also more serious sexual assault, aggravated burglary cases over the course of the year. It really covers the whole gamut of offences."

The DNA Database Oversight Committee also states in the report that the "operation of the DNA Database System continues to be very successful due in large part to the hard work and professionalism of the Director and staff of Forensic Science Ireland (FSI) and the staff of the National Forensic Coordination Office (NFCO)(a section of the Garda National Technical Bureau) notwithstanding the significant challenges presented to both bodies by the pandemic".