Saturday, January 18, 2020

A Fourth Model of Law Enforcement Access to DNA Databases

First there were DNA databases of four or five RFLP VNTR measurements obtained by gel electrophoresis of the DNA fragments of convicted offenders. These were soon superseded by much larger databases for convicted-offenders (and later, arrestees) comprised of a larger number of STRs determined with capillary electrophoresis. The individuals supplying the DNA analyzed in these limited ways had no choice in the matter. Statutes compelled them to submit to DNA sampling, and only law enforcement authorities had access to these special-purpose, government-run databases.

In recent years, the potential for private databases to generate investigative leads through trawling (without individualized suspicion or probable cause) has begun to be exploited. Millions of SNP-based records reside on the servers of recreational genetics companies that process saliva samples with SNP arrays that determine the alleles present at hundreds of thousands of SNP loci. The customers of each direct-to-consumer (DTC) testing company can learn if other participating customers of that company have large blocks of DNA in common -- a situation indicative of a family relationship. (Other tests for relatedness in the private databases are also possible, but the haploblock-matching procedure has been the most productive for criminal investigations because it casts a wider net.) In addition, over a million samples reside in the voluntary private database known as GEDmatch, which enables genealogy enthusiasts to share their personal SNP-array data.

SNP-array testing does not work well with crime-scene DNA samples that contain mixtures of DNA from several individuals, that are severely limited in quantity, or that are degraded. However, an alternative technology, known as massively parallel, or next generation sequencing (MPS or NGS), can generate genomic data from challenging samples, and the sequence data can be culled to supply the SNP-array data that DTC companies would have provided had the source of the DNA evidence from the crime-scene sent a saliva sample in to one of these companies. Armed with such a data file, police who are able to access a DTC or GEDmatch-type database can look for potential relatives. By turning to these individuals (or public records about the families), police sometimes can find a suspect who merits further investigation.

Many DTC customers who did not realize their DNA might lead police to their relatives (known or unknown to them) have found this kind of forensic genomic genealogy (FGG) profoundly disturbing, at least when it was not something they had explicitly signed up for. Others have evinced less concern. The private database operators have responded with different policies. GEDmatch presumes that users object, but allows them to indicate their willingness to have their data used in law-enforcement trawls. Another possible response is an opt-out policy, in which the presumption is that individuals are not opposed to this use of their data. Yet another policy is that the database is always open to law enforcement, just as it is to curious individuals. Finally, the database could be completely closed to law-enforcement trawling (without judicial approval based on a showing of individualized cause).

In short, there are three main models of law enforcement access: (1) the government-run, law-enforcement-only database; (2) the private other-purpose, opt-in database; and (3) the private other-purpose, opt-out database. However, a fourth model is emerging -- a privately run law-enforcement-only database.

An article from the information service GenomeWeb reports on the plans of Othram, which bills itself as "the first technology company to apply all the power of modern sequencing and genomics to forensics" so as to secure "justice through genomics." The article includes a number of interesting statements from the company's CEO, David Mittelman. GenomeWeb explains that
Othram ... introduced DNASolves.com to solicit users of consumer genomics services to upload their data for the expressed desire to help law enforcement solve cold cases.

"Family Tree DNA is doing the opt-out model [with regards to law enforcement], GEDmatch is doing opt-in," said ... Mittelman. "I thought there should be another model," he said. "Since we do nothing but law enforcement, there is nothing to opt out of."

Mittelman, a former CSO at Family Tree DNA parent Gene by Gene ... said "I have enjoyed the consumer genetics and genealogy side, and I certainly enjoyed the medical side, but I saw the forensics market as a market that was underserved and could benefit from the technology that has been widely used and embedded in consumer and medical testing," he said. "It made sense to bring that technology over."

Mittelman credited the developments in the market with both the success of consumer genomics as well as advancements in next-generation sequencing technology. By some estimates, 30 million people have taken an array-based consumer test to date. Meantime, the drop in the price of sequencing, plus ongoing innovation in the field, means that it is now possible to perform whole-genome sequencing of highly degraded samples from crime scenes and then scour large databases to find genetic relatives, constructing genealogies to identify victims or perpetrators.
...
"In 2019, sequencing failed to penetrate the consumer market," said Mittelman. "But forensics is an interesting market where sequencing is superior to arrays," he said. "It is not just that sequencing gives you more information, in a lot of cases it's the only way to get information," he added.
Othram's approach is called Forensic Grade Genome Sequencing. According to Mittelman, array technology has a "high failure rate" when it comes to forensic samples, making sequencing the go-to technology when it comes to working with these kinds of samples.

"You really need special methods," said Mittelman. "We have developed proprietary methods to adapt the worst kinds of DNA to sequencing," he added. "I think in the long term forensics will only work with sequencing, while for consumer, arrays are good enough."

Othram has not yet published on its techniques, but eventually aims to do so, Mittelman said. While the company hones its sequencing capabilities, it is also hoping more customers of consumer services will be moved to upload their data to DNASolves.com. He noted that only a small percentage of those tested have elected to upload data to GEDmatch, meaning the potential exists to grow a new database of a different set of users interested in helping law enforcement.

"Rather than target a small number of people who are genealogy power users, and ask them to help solve crime instead, it seemed to me that you could approach the 30 million who have tested and tell them if you have tested and feel like getting involved, this is how you do it," said Mittelman. "You don't have to be a power user in genealogy to make a difference in crime solving."
Whether DNAsolves.com will attain the critical mass to be a useful investigative database is not guaranteed, so it is not clear that the data donors will be "making a difference in crime solving." Buut even if the database remains small, Othram can market its FGG service as offering the police agency access to a exclusive database. In a seeming excess of enthusiasm about finding "the most distantly related individuals," the website states that
We are all genetically related to one-another [sic]. Genetic genealogy uses DNA information in combination with genealogical and historical records to establish relationships between even the most distantly related individuals. This is a substantial improvement in human identification capability from current forensic testing methods that enable exact or near exact matches. When you contribute your DNA data, you help identify victims, missing persons, and perpetrators of crimes — even if you are a distant genetic relative.

REFERENCE

Justin Petrone, Forensic Genomics Market Advances Due to Consumer Databases, Technology Innovation, genomeweb, Jan. 9, 2020, https://www.genomeweb.com/sequencing/forensic-genomics-market-advances-due-consumer-databases-technology-innovation

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