Montgomery County's First Familial DNA Solve: The Science Behind the Leslie Preer Case

Chevy Chase, Maryland is not the kind of place that usually makes headlines for unsolved murders. It is an affluent, close-in suburb that straddles the DC border — the kind of neighborhood where residents expect institutions to function, crimes to be solved, and justice to arrive in a reasonable timeframe. When Leslie Preer was murdered in her Chevy Chase home on May 2, 2001, the assumption was probably that it would be solved. She was 49 years old. She was a mother. The crime was violent and local. These cases get solved.

Twenty-three years later, the chevy chase cold case dna result that finally identified her killer illustrated something that investigators and forensic scientists have been saying for years: no case is too old, and the science is now better than the science was when the crime was committed.

What makes the Leslie Preer case genuinely significant — beyond the particular tragedy of one family’s loss and one perpetrator’s accountability — is that it produced a first. Montgomery County, one of Maryland’s largest and best-resourced county law enforcement agencies, identified this as its first-ever familial DNA cold case solve. That designation has technical meaning, and it is worth unpacking.

Why CODIS Wasn’t Enough

Traditional DNA evidence in criminal cases works through CODIS — the Combined DNA Index System, the national database maintained by the FBI. When investigators collect DNA from a crime scene and need to identify an unknown contributor, they search CODIS. If the perpetrator has a prior arrest or conviction that resulted in a DNA sample being taken, that sample is in CODIS, and the search returns a match. If the perpetrator has no criminal record, CODIS returns nothing. The case goes cold.

Eugene Gligor had no prior criminal record that would have placed him in CODIS. For twenty-three years, the crime scene DNA sat as an unidentified profile. Standard investigative avenues had been exhausted. The case was cold.

The Othram Pathway

The transformation of this chevy chase cold case dna investigation began when Montgomery County detectives submitted the crime scene sample to Othram, a forensic genomics laboratory in The Woodlands, Texas that specializes in recovering usable DNA profiles from degraded or low-quantity samples. Othram’s next-generation sequencing technology enhanced the crime scene DNA into a profile suitable for investigative genetic genealogy — a process abbreviated as IGG.

IGG is not a single-step process. It is a workflow. Othram ran the enhanced profile through opt-in genealogy databases — specifically, databases whose users have consented to law enforcement use, such as GEDmatch, FamilyTreeDNA, and DNASolves (Othram’s own law enforcement-exclusive platform). To be precise about what these databases are not: they are not AncestryDNA, and they are not 23andMe. Neither of those commercial platforms permits law enforcement database searching, and neither was involved in this investigation.

The opt-in databases returned genetic relatives of the unknown DNA contributor. Genealogists built a family tree from those results — in this case, a Romanian family tree, because Gligor’s background is Romanian. The tree produced investigative leads. One of those leads pointed directly to a name that Montgomery County detectives had written in the original case file in 2001: Eugene Gligor, the teenage ex-boyfriend of Leslie’s daughter Lauren.

The database did not identify Gligor. The database returned relatives. The genealogists built the tree. The detectives recognized the name. That sequence matters because it illustrates what IGG actually is: a biological inference engine that produces leads for human investigators to develop, not a digital fingerprint scanner that returns a suspect’s name.

The Confirmation

Confirmation came through a covert collection. Detectives obtained a water bottle that Gligor had discarded — legally abandoned property, collectible without a warrant — and subjected it to STR analysis, the standard short tandem repeat profiling method used in forensic DNA comparison. The STR profile from the water bottle matched the crime scene DNA. That match, not the genealogy database result, formed the evidentiary core of the case against Gligor.

He pleaded guilty in May 2025 in Montgomery County Circuit Court and was sentenced to 22 years in prison plus 5 years of supervised probation on August 28, 2025.

Why This First Matters

Why does Montgomery County’s first matter beyond the county line? Because the forensic genealogy wave is still early. Jurisdictions across the country are at different stages of adopting IGG as an investigative tool — some have built dedicated units, others are contracting with Othram and similar labs on a case-by-case basis, and others have not yet used it at all. Each first — each county’s first familial DNA cold case solve, each state’s first successful prosecution built on IGG leads — adds to the record of what the methodology can achieve and under what conditions courts will accept the resulting evidence.

Maryland now has a prominent, fully adjudicated example. A case that was cold for twenty-three years, in an affluent community that expected justice and did not get it for two decades, is now closed. The methodology that closed it is replicable. The science that made the DNA enhancement possible is commercially available to law enforcement agencies. The genealogy databases that provided the family tree leads are populated by people who chose to upload their profiles and consent to this use.

What the Leslie Preer case demonstrates, at the technical level, is that the combination of next-generation sequencing and opt-in genealogy databases can reach perpetrators who have no criminal record, no CODIS profile, and two decades of apparent immunity. That is the actual significance of what happened in Chevy Chase.

The genealogy was the lead. The STR match was the proof. The case is closed.

For more sourced, victim-first true crime from Cassian Creed, read The Trail — the full-length case file on the murder of Rachel Morin, $1.99 on Beehiiv.

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