Studies show consumer genealogy databases are much broader than is generally known. If your cousins are in such a database, it’s likely you are too

Recent news stories highlighted crime investigators who used the DNA data in consumer genetic genealogy databases to solve cold cases. Though not widely known, such uses of direct-to-consumer DNA databases is becoming more commonplace, which might eventually lead to requests for clinical laboratories to assist in criminal investigations involving DNA data.

Case in point: investigators found the Golden State Killer, a serial killer/rapist/burglar who terrorized multiple California counties over a dozen years in the 1970s to 1980s, after uploading a DNA sample from the crime scene to GEDmatch, an open-data genomics database that features tools for genealogy research. They made the arrest after discovering a distant relative’s DNA in the genealogy database and matching it to the suspect, CBS News revealed in a 60 Minutes Overtime online report.

These and other investigators are using a technique called familial DNA testing (AKA, DNA Profiling), which enables them to use genetic material from relatives to solve crimes.

Clinical laboratories oversee DNA databases. Could DNA databases—developed and managed over years by medical laboratories for patient care—be subpoenaed by law enforcement investigating crimes?

The question raises many issues for society and for labs, including privacy responsibilities and appropriate use of genetic information. On the other hand, the genetic genie is already out of the bottle.

Leveraging Familia DNA to Solve Crimes a New Trend

“The solving of the Golden State Killer case opened this method up as a possibility, and other crime labs are taking advantage of it. Clearly, a trend has started,” Ruth Dickover, PhD, Director of Forensic Science, University of California, Davis, told the Los Angeles Times.

Indeed, the use of familial DNA testing is moving forward. The Verge reported 19 cold case samples have been identified in recent familial DNA testing and public database searches. It also said two new published studies may propel the technique further.

One study, published in the journal Science, suggests nearly every American of European ancestry may soon be identified through familial DNA testing.

The other study, published in Cell, shows that a person’s relatives can be detected when forensic DNA data are compared with consumer genetic databases.

Professor Noah Rosenberg and postdoctoral research fellow Jaehee Kim.

Noah Rosenberg, PhD (above left), Professor of Population Genetics and Society Biology at Stanford University, is shown above working with Jaehee Kim, PhD (right), a Postdoctoral Research Fellow in Biology, on math that could be used to track down relatives in genealogy databases based on forensic DNA. “This could be a way of expanding the reach of forensic genetics, potentially for solving even more cold cases. But at the same time, it could be exposing participants in those databases to forensic searches they might not have anticipated,” he told Wired. (Photo copyright: Stanford University/L.A. Cicero.)

15 Million People Already in Genealogy Databases

Researchers at Columbia University in New York and Hebrew University of Jerusalem told Science they were motivated by the recent trend of investigations leveraging third-party consumer genomics services to find criminals. But they perceived a gap.

“The big limitation is coverage. And even if you find an individual it requires complex analysis from that point,” Yaniv Erlich, PhD, Associate Professor at Columbia and Chief Science Officer at MyHeritage, told The Verge. MyHeritage is an online genealogy platform.

Others offering consumer genetic testing and family history exploration include 23andMe and Ancestry. As of April 2018, more than 15 million people have participated in direct-to-consumer genetic testing, the researchers noted.

The study aimed to find the likelihood that a person can be identified using a long-range familial search. It included these steps and findings:

  • Statistical analysis of 1.28 million people in the MyHeritage database;
  • Pairs of people with “identity-by-descent” were removed to avoid bias, such as first cousins and closer relationships;
  • Researchers aimed at finding a third cousin or closer relatives for each person in the database;
  • 60% of the 1.28 million people were matched with a third cousin or closer relative.

“We project that about 60% of the searches for individuals of European-descent will result in a third cousin or closer match, which can allow their identification using demographic identifiers. Moreover, the technique could implicate nearly any US individual of European descent in the near future,” the researchers wrote.

In an interview with Wired, Erlich added, “The takeaway is it doesn’t matter if you’ve been tested or not tested. You can be identified because the databases already cover such large fractions of the US—at least for European ancestry.”

Matching Forensic and Consumer Genetic Data

Meanwhile, the study published in Cell by researchers at Stanford University, University of California, Davis, and the University of Michigan also suggests investigators could compare forensic DNA samples with consumer genetic databases to find people related to criminals.

That study found:

  • 30% to 32% of people in a forensic database could be related to a child or parent in a consumer database;
  • 35% to 36% could be tied to a sibling.

These studies reveal that genetic data and familial DNA testing can help law enforcement find suspects, which is a good thing for society. But people who uploaded DNA data to some direct-to-consumer databases may find themselves caught up in searches they do not know about. So may their cousins.

Dark Daily recently covered other similar studies that showed it takes just one person’s DNA to reveal genetic information on an entire family. (See, “The Problems with Ancestry DNA Analyses,” October 18, 2018.) These developments in the use of DNA databases to identify criminals should be an early warning to clinical laboratories building databases of genetic information that, at some future point, law enforcement agencies might want access to those databases as part of ongoing criminal investigations.

—Donna Marie Pocius

Related Information:

Could Your DNA Help Solve a Cold Case?

So Many People Have Had Their DNA Sequenced That They’ve Put Other People’s Privacy in Jeopardy

The DNA Technique That Caught the Golden State Killer is More Powerful than We Thought

Identity Inference of Genomic Data Using Long-Range Familial Searches

Statistical Detection of Relatives Typed with Disjoint Forensic and Biomedical Loci

Genome Hackers Show No One’s DNA is Anonymous Anymore

Stanford Researchers Discover a New Way to Find Relatives from Forensic DNA

The Problems with Ancestry DNA Analyses