The family of the New York City jogger raped and killed during a run last summer in Queens is calling on the state to employ the familial DNA matching system in the state, Fox5Ny.com reported.

The database is controversial because of privacy concerns, but would possibly lead to a match If the suspect’s relative is in the correctional system.

The genetic fingerprint didn’t match any of the profiles from convicted criminals in the state’s Combined DNA Index System. A check against the FBI’s DNA database also came up empty.

So for now, investigators are relying on traditional investigative techniques to try to identity Karina Vetrano’s killer, while the DNA sample joins 56,530 others on file with the state that have been lifted from crime scenes but have so far not been linked to a person.

“I would bet that in at least half of (DNA) cases, they get a suspect from analysis and their job becomes easy,” said Dan Krane, a DNA expert at Wright State University in Dayton, Ohio. “But in the other half, they have to resort to old-fashioned detective work.”

Vetrano’s killing has been an object of tabloid fascination in New York ever since her father, a retired firefighter, discovered her badly beaten body in a marshy park not far from her home on Aug. 2. She normally ran a route through the area with her dad, but an injury kept him from joining her that evening.

Investigators have interviewed cyclists and runners who frequent the Spring Creek Park trails, combed through Vetrano’s personal life for clues and even checked shoplifting and panhandling reports at a nearby mall as part of the hunt for the killer. They have also been examining convicted sex offenders who were imprisoned before the state DNA database was established in 1996, according to the police.

To preserve a path to prosecution, district attorneys in many states, including Ohio, Arkansas, Delaware and New York, have made a practice of securing criminal indictments in rape cases of “John Doe” defendants, who have been identified only by their DNA profiles.

That legal strategy was devised to stop the clock on statutes of limitation for sex crimes, but it also points to the frequency of instances where investigators have DNA but no suspect.

State and federal authorities regularly run comparisons against DNA databases to see if there are new hits.

There is no statute of limitation on murder — but the lack of a DNA hit makes Vetrano’s case harder to solve.

“The bottom line is, unless there’s other evidence that we don’t know about, if it’s just DNA, they’re in trouble,” Lawrence Kobilinsky, a DNA expert who chairs the science department at John Jay College for Criminal Justice said at the time. “They’re going to have to wait until this guy makes a mistake.”

The Associated Press contributed to this report