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Experts: Advances in DNA technology helped lead to arrest in Gilgo Beach murders

Retired New York City Detective David Sarni says with advances in DNA analysis, hairs, fingernails, blood stains and other sources of DNA do not have to be in pristine condition for investigators to find a match.

Jul 20, 2023, 10:25 PM

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Experts say breakthroughs in DNA technology have played a huge role in making an arrest in the Gilgo Beach murders.

Retired New York City Detective David Sarni says with advances in DNA analysis, hairs, fingernails, blood stains and other sources of DNA do not have to be in pristine condition for investigators to find a match.

LIVE BLOG: Updates on the case as they happen 

He says this was key in the Gilgo Beach investigation.

"You're dealing with burlap sacks with bodies in them left for an extended periods of time with nature to affect them," Sarni says.

MORE: ‘It just shrunk that whole universe.’ Pickup truck proves to be key piece of evidence that led investigators to Gilgo suspect, state police say

Suffolk County District Attorney Ray Tierney says that suspect Rex Heuermann's home and vehicle are being searched for evidence "inch-by-inch."

Sarni, who is also an adjunct professor at John Jay College of Criminal Justice, says that is no exaggeration.

WATCH: DOCUMENTARY AND BACKGROUND INFORMATION - Gilgo Beach: Unsolved

"If there's a chance you could retrieve some sort of sample from whatever evidence you locate, then you do it," Sarni says.

Sarni says DNA evidence was one piece of the puzzle in arresting Heuermann for three of the Gilgo Beach murders.

MORE: ‘How could that happen?’ Neighbors shocked as sources say investigators believe at least 1 Gilgo Beach murder happened at suspect’s home

He says investigators worked on the case prior to DNA evidence and are continuing to work on it.

MORE: Sources: Investigators believe at least 1 of Gilgo Beach murders took place at suspect's Massapequa Park home


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