ABC News November 6, 2018

'I honestly never thought they would find him': DNA test, genetic genealogy lead to arrest in woman's 2001 killing

WATCH: Genealogy test leads to arrest in 2001 murder, police say

An Orlando, Florida, man is behind bars and accused of killing a young woman 17 years ago, after police say he was identified through genetic genealogy.

Authorities arrested Benjamin Holmes on Friday for the slaying of 25-year-old college student Christine Franke, who was killed in her Orlando apartment on Oct. 21, 2001, Orlando police said Monday.

Orlando Police Department
The Orlando Police Department arrested Benjamin Holmes in connection with the death of Christine Franke, Nov. 5, 2018. The police used a DNA sample from the crime scene to develop a DNA profile and composite image of the suspect which led to the arrest.
(MORE: How DNA and genetic genealogy are becoming 'major' game-changers in decades-old cold cases)

"I honestly never thought they would find him," Christine Franke's mother, Tina Franke, said at Monday's news conference in Orlando as the arrest was announced.

"This is such a happy day for us," she said, adding that she was "overwhelmingly grateful" for the investigators who "never gave up on my daughter's case."

(MORE: DNA, genetic genealogy led police to suspected killer in Maryland cold case)

Though DNA was left behind at the 2001 crime scene, years went by without an arrest.

A few years ago, through DNA technology, authorities were able to release a composite sketch of a possible suspect, but investigators didn't get any leads based on the image, police said.

Orlando Police Department
The Orlando Police Department arrested Benjamin Holmes in connection with the death of Christine Franke, Nov. 5, 2018. The police used a DNA sample from the crime scene to develop a DNA profile and composite image of the suspect which led to the arrest.
(MORE: DNA on napkin led to arrest in cold-case 1986 rape and murder of 12-year-old girl)

Police said the case was finally cracked this year through genetic genealogy, a technology in which an unknown killer's DNA from a crime scene can be identified through his or her family members, who voluntarily submitted their DNA to a genealogy database. This allows police to create a much larger family tree than using regular law enforcement databases like CODIS, in which an exact match is needed in most states, according to experts. In the case of Holmes, one person in his family who was interested in family history and genealogy entered into the GEDmatch database in the hopes of finding additional relatives she didn’t know about, according to Orlando police.

Authorities have identified suspects in over a dozen crimes across the country this year thanks to genetic genealogy, including the April arrest of the suspected "Golden State Killer," Joseph James DeAngelo, -- a cold case that stumped California law enforcement for decades.

In the case of Christine Franke, some of Holmes' family members had submitted their own DNA to the GEDMatch database when using DNA testing websites, police said, which allows authorities to access the information. Investigators also went to several of Holmes' family members who voluntarily gave them samples, police said.

(MORE: How DNA led to arrest in cold-case killing of Indiana 8-year-old after it 'haunted the community for 30 years': Prosecutor)

Eventually Holmes was served with search warrant for his DNA which was determined to be a match to the crime scene DNA, police said.

It appears Holmes and Christine Franke did not know each other prior to the crime, police said.

WFTV
The Orlando Police Department arrested Benjamin Holmes in connection with the death of Christine Franke, Nov. 5, 2018. The police used a DNA sample from the crime scene to develop a DNA profile and composite image of the suspect which led to the arrest.

Holmes, 38, of Orlando, was taken into custody Friday, charged with first-degree murder with a firearm and robbery with a firearm, according to records.

When arrested Holmes "denied having any knowledge or being near the crime scene," according to police.

He has not yet entered a plea.

His public defender, Chelsea Simmons, declined to comment to ABC News.

Meanwhile, Christine Franke's mother told reporters Monday that she hopes genetic genealogy technology helps more families.

"It's a terrible thing, not knowing," she said.