Law enforcement is likely using a novel DNA analysis tool in their search for the man who murdered mother-of-five Rachel Morin on a Maryland hiking trail last month, experts told Fox News Digital.
Police don't have a suspect, but they do have the DNA he left behind. The Harford County Sheriff's Office matched his DNA to a home invasion and assault of a young girl in Los Angeles in March.
"So, the person has not been identified, but we know he's responsible for two separate crimes," said CeCe Moore, a DNA detective with Parabon NanoLabs. "This is the perfect application of investigative genetic genealogy."
The technique, which identified the Golden State Killer, uses traditional DNA analysis and public records to build family trees and zero in on suspects.
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Moore, who has solved more than 250 cases through DNA analysis, described the tool as a "tip generator."
It has traditionally been used to close cold cases, but Moore has long advocated a broader application.
"When you can stop a criminal in his tracks and prevent him from victimizing more people, that is really the best use," she said.
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She suspects that the FBI, which has its own investigative genetic genealogy unit, is using this very method to try to find Morin's killer.
Morin, 37, went for a hike on Aug. 5 about 6:30 p.m. on the Ma and Pa Heritage Trail in Bel Air, Maryland, but didn't return. The next day, her body was found in a wooded area on the side of the path.
Authorities uploaded the suspect's DNA to CODIS, a national database that includes DNA evidence from unsolved crimes, and there was a hit to the Los Angeles assault.
The Los Angeles Police Department released surveillance video of the suspect leaving the home and described him as Hispanic, in his 20s, 5-foot-9 and 160 pounds.
The next step for genetic investigators is to upload the DNA sample to GEDmatch and FamilyTreeDNA, which have databases of about 2.5 million people.
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They cooperate with law enforcement, unlike the major commercial databases, Ancestry.com and 23andMe, which have more than 30 million contributors.
"If this man really is Hispanic or Latin American, then it's likely going to be a much more difficult case," Moore said.
Another investigator with Parabon NanoLabs, who specializes in Hispanic cases, told Fox News Digital why these genetic puzzles are harder to solve.
The DNA detectives start with the closest genetic hits they get in the DNA databases, which often are distant cousins. They then build family trees starting with the most distant relatives and working forward with the help of public records and other data.
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But Hispanics are underrepresented in the databases, making it less likely a DNA profile will match a close relative, said the investigator, who asked to remain anonymous given her work identifying dangerous criminals.
The exception is Mexican-American families whose presence in the U.S. goes back to the 1800s.
In addition, if the suspect is a recent immigrant it's even less likely they'll get a close match, she said. If the suspect is an undocumented immigrant, the trail can go cold quickly.
For recent immigrants, the family trees will extend outside the U.S., and the DNA investigator must be fluent in Spanish to access and read census and vital records.
But an even greater hurdle that is unique to the Hispanic community is the lack of diversity of surnames, the scientist said.
"When we're building trees for these distant DNA matches, we are trying to figure out where these trees are connected to each other," she said.
"When we see that other surname in another tree, we can say, ‘Aha.’ This might be where that tree connects."
But with Hispanic families, it's just as likely that a repeat of a surname is a coincidence.
She cited a European study to illustrate this point. In Spain, 20% percent of people in the country have one of the 10 most common surnames.
In comparison, in Italy, just 0.6% of the population uses the 10 most common surnames. Most Spanish immigrants who settled in the New World came from the southern half of Spain.
Harford Sheriff Jeff Gahler declined to comment on whether officials are using investigative genetic genealogy to try to solve the case.
Local authorities are asking anyone with information on Morin's murder to call 410-836-5430 or email RMTips@harfordsheriff.org.
