One in five crimes will now be solvable as a result of the DNA database, which is managed by Forensic Science Ireland (FSI),.
Tánaiste and Justice Minister Frances Fitzgerald turned the sod on the FSI's state-of-the-art €60m facility this morning in Cellbridge, Co Kildare.
The new laboratory will serve to enhance the analysis of crime scene evidence.
"In 2015, the much-awaited DNA database was established. It's fair to say that is has been way more successful than we could have imagined. The take-up has been phenomenal," said Dr Sheila Willis, the director general of the FSI.
"We have a one-in-five chance of an unsolved crime matching a person on the database and that will even change and grow as we go along," she added.
The Tánaiste said the facility, which is now starting one year ahead of schedule, will help to "future proof" Ireland's "justice infrastructure".
"This new much-needed facility will help to future proof an essential part of our justice infrastructure," said the Tánaiste.
FSI currently has a staff of just over 100 people working out of laboratories at Garda headquarters in the Phoenix Park.
The new laboratory, at 9,550 square metres, is on the Backweston campus and is due for completion in 2020/2021.