The family of Trevor Deely, who disappeared 18 years ago on Saturday, say their next step will be to see if modern DNA extraction technology could be used to generate some leads which would finally help trace his whereabouts.
His sister Michele Deely said new technology could be applied to previously unidentified human remains.
The new technology was successfully used last year to identify the partial remains of Gussie Shanahan, who went missing from Limerick in 2000.
"We're talking to the guards about it at the moment to see if there is anything there we can use to progress it," Ms Deely said. A meeting between the family and representatives from Forensic Science Ireland is being set up, she said.
Trevor’s father Michael said the family are “realistic” about what happened to Trevor but will hold out hope he is alive “until we are told otherwise”.
Michele said “there is a difference between what is possible versus what is probable. But stranger things have happened.”
A review into Trevor’s disappearance concluded earlier this year without producing any new leads. While his family were informed of this last April, they are still hopeful that someone may come forward with new information or that advances in DNA technology might lead to a breakthrough in the case.
The cold case review, which was instigated at the behest of the Deely family, involved a team of six detectives re-interviewing dozens of people and reviewing all the old case files.
Enhanced CCTV footage from the early hours of December 8th, 2000, showing 22-year-old Trevor speaking to an unidentified man at the Bank of Ireland on Haddington Road, was also released, but it failed to yield any information.
“This was our biggest fear. That we would go through this and there would be nothing. Because we did have a sense of hope because it was a very expert, committed team who put their heart and souls into it,” Michele said.
“That’s the end of that route. Trevor is a missing person so his case is always open, but it’s now completely reactive to anything incoming.
“As a family we have tried to be as proactive as you can possibly be, but I just feel lost. What do you do next?”
The cold case review was unconnected to the search of a 12-acre site in west Dublin last year for Trevor’s remains. The search did not produce any leads.
Ms Deely explained that the search came about because of a tip-off received by the Garda and not as a result of the review. Gardaí believe the tip-off was made in good faith.
“It turned out to be wrong. So we’re back to square one,” she said. “You go through such a gruesome experience and ordeal in the public eye and then you still end up with nothing whatsoever.”
When the dig began last year there were various theories in the media about what happened to Trevor, including that he was murdered by a well-known criminal.
His sister said this was very difficult for the family and that they never heard these theories from the gardaí involved.
“We’ve garnered such attention from the public for Trevor so we have to take that. But that was horrible.” She said she had to explain to her 10- and six-year-old children that they couldn’t believe everything they read about “Uncle Trevor”.
There is still a €100,000 reward for information relating to Trevor’s disappearance. Anyone with information can contact the Crimestoppers anonymously on 1800-250025.