Authorities investigating the murders of four University of Idaho students are likely using forensic genetic genealogy — comparing DNA evidence to genealogical family databases, an expert said in a new interview.
Idaho State Police Forensic Services is testing 113 pieces of physical evidence collected at the bloody scene, Fox News reported.
Experts typically start by comparing unknown DNA samples to the FBI’s Combined DNA Index System — or CODIS, a database containing genetic samples of known criminals — using STR (short tandem repeat) DNA analysis.
“It is quite fast compared to CODIS. Had they gotten a match, I think they probably would have been arrested by now, so I think we can assume they’re at least looking at using exploratory genetic genealogy,” CeCe Moore, chief genetic genealogist at Parabon NanoLabs in Reston, Va., told Fox News Digital.
“It just depends on how quickly they learned they didn’t have a match in CODIS as to when it would be done,” added Moore, one of the most successful genetic genealogists working in law enforcement in the United States.
If the preliminary analysis falls short, investigators can analyze more than half a million DNA single nucleotide polymorphisms, or SNPs, in the search for possible distant relatives of a suspect, Fox News reported.
Experts can reverse-engineer a person’s family tree using traditional genealogy and narrow it down to a possible suspect from whom they can surreptitiously try to extract a DNA sample, according to the news outlet.
Moore and her team recently used genetic genealogy to analyze DNA in the 1975 murder of Lindy Sue Biechler, 19, in Pennsylvania.
Male DNA was recovered from the victim’s underwear, but investigators did not get a hit in CODIS.
The researchers at Parabon Labs secretly obtained fresh DNA from a coffee cup that a suspect threw in the trash earlier this year.
The sample came back as a match for DNA taken from the crime scene — leading to the arrest of David Sinopoli, 68, who now faces murder charges, Fox News reported.
“They always need that extra step of collecting DNA, and it’s usually going to be covert because they don’t want to tip anybody off,” Moore said.
Investigators can often obtain DNA samples from a killer who used a knife to commit a crime.
“Typically, in cases that I’ve worked with stabbings, if someone stabs enough times, the knife almost always slips,” Moore told Fox News Digital.
“You almost always get the perpetrator’s DNA mixed with the victim’s DNA,” she added.
Meanwhile, Matthew Gamette, the director of Idaho State Police Forensic Services, warned that investigations are time consuming.
“I certainly can’t share case-specific information,” Gamette told the Idaho Statesman. “I can tell you that our researchers are working very hard.
“These things do not necessarily appear in the media. Investigators are getting information that will hopefully be helpful to their investigation and we will continue to work at the state lab as we do 365 days a year,” he added.
State police spokesman Aaron Snell told the newspaper that investigators are still receiving analyzes and test results from the state lab.
Officials have previously said the results will not be released to the public, according to the Statesman.
Gamette said it is critical that investigators receive a “DNA profile” from cells in the body to help identify a suspect through genetic makeup.
In Idaho, the CODIS database includes DNA from convicted felons and evidence from other crime scenes, he told the newspaper.
Investigators can also turn to the national database, whose records from some states include not only felons but also people arrested on suspicion of a crime, Gamette added.
As for the use of molecular forensic genetic genealogy, Gamette said the state crime lab doesn’t have the cutting-edge technology, but noted it could contract for the work.
He declined to comment to the Statesman on any details related to the murder investigation.
On Wednesday, police revealed they were looking for the occupants of a white Hyundai Elantra who may have “critical information” about the quadruple homicide that claimed the lives of Kaylee Goncalves, 21, Madison Mogen, 21, Xana Kernodle, 20, and Kernodle. boyfriend Ethan Chapin, 20.