There are several issues related to medical privacy and forensic samples that have been raised and debated over the years. One of the main concerns is that forensic samples, such as DNA samples, can contain sensitive personal information about an individual’s genetic makeup and medical history. This information can potentially be accessed and used for purposes that the individual did not consent to, such as genetic testing or insurance discrimination.
Another concern is that forensic samples may not always be collected and stored with the same level of security and confidentiality as medical samples. For example, some forensic samples may be collected in public places or from crime scenes, which could potentially expose them to tampering or unauthorized access.
Any episode of “CSI” will feature a character using forensic DNA profiling to identify a criminal. Contrary to what the legal community has believed for nearly 30 years, a new study from San Francisco State University suggests that these forensic profiles may indirectly reveal medical information – possibly even that of crime victims. The findings may have ethical and legal consequences.
“The main assumption when selecting those [forensic] markers was that there would be no information about the individuals other than identification. That assumption is challenged in our paper” Mayra Bauelos (B.S., ’19), who began working on the project as a San Francisco State undergraduate and is now a Ph.D. student at Brown University, is the project’s first author.
The Combined DNA Index System (CODIS) is a system that organizes criminal justice DNA databases and uses specific genetic markers to identify individuals. National, state, and local crime labs contribute to these databases by providing profiles based on samples collected from crime scene evidence, convicted offenders, felony arrestees, missing persons, and other information. The database can be used by law enforcement to try to match samples discovered during an investigation to profiles already stored in the database.
The main assumption when selecting those [forensic] markers was that there would be no information about the individuals other than identification. That assumption is challenged in our paper.
Mayra Bauelos
CODIS profiles are made up of an individual’s genetic variants as a set of short tandem repeats (STRs), which are DNA sequences that repeat at different frequencies among individuals. Since the 1990s, 20 STRs have been selected for forensic CODIS profiling because it was thought they did not relay medical information. If these profiles contained any trait information, then there could be issues about medical privacy.
“But that assumption hasn’t had many investigations in a long time, and we know a lot more about the genome now than we did back then,” explained SF State Associate Professor of Biology Rori Rohlfs, who led this project.
The assumption that only criminals are sampled is also incorrect. “It actually includes crime victims and people who may have been present at crime scenes. You have these massive databases with a lot of people who aren’t necessarily criminals in them “According to Baelos. “I also believe that access to these databases varies greatly depending on jurisdiction.”
Other papers have found associations between other (non-CODIS) STRs and disease or gene expression, according to the researchers. With this in mind, the SF State researchers wanted to learn more about the relationship between CODIS STR markers and gene expression.
Rohfls’ lab used publicly available data (1000 Genome Project) and genetic models to investigate the relationship between CODIS markers and gene expression. Of the 20 CODIS markers, they found six associations between CODIS markers and gene expression of nearby genes in white blood cell lines from more than 400 unrelated individuals in the database.
“In some genes, gene expression change has been associated with medical conditions,” Bañuelos explained, citing prior research. “[In this study,] we indirectly know there is an association between these CODIS genotypes and some change in genes that can lead to illness.”
The authors highlight three intriguing gene associations (CSF1R, LARS2, and KDSR). Previous research has linked CSF1R mutations and changes in gene expression to psychiatric conditions (depression and schizophrenia). Mutations and changes in gene expression in other genes have been linked to Perrault syndrome, MELAS syndrome, severe skin and platelet conditions, and more, according to the researchers in the PNAS (Proceedings of the National Academy of Sciences) paper. If CODIS markers are linked to the expression of genes associated with disease and health, the data in the CODIS database may jeopardize an individual’s medical privacy.
“Our paper is like the tip of the iceberg in some ways,” Rohlfs explained, admitting that she was surprised to find associations in such a small sample size. The project began as an undergraduate research project. When the project began, eight of the 11 authors, including Bauelos, were undergraduates at SF State.
“It begs the question: Would we find even more information revealed by CODIS profiles if we did a larger [genetic] study?” Rohlfs was curious. Baelos and Rohlfs want to know what they’d find if they looked at a larger dataset with a more diverse population mix – their current dataset is primarily European. They also limited their investigation to white blood cells. What relationships would they find if they looked in other tissues?
These are critical lines of inquiry because the current dataset does not represent the general population. Furthermore, Latino and African American communities, according to Bauelos, are overrepresented in CODIS databases. More research is needed to fully comprehend the relationship between CODIS and medical data. However, the researchers warn that if CODIS profiles contain medical information, serious consequences may result.
“If [these CODIS profiles] contain medical information, they must be treated in accordance with how medical information is protected in the United States. Policies governing the seizure, storage, and sharing of these profiles would be required” Rohlfs went on.
