Australian police linking DNA to ancestry could be a privacy nightmare

The Australian Federal Police recently announced plans to use DNA samples collected at crime scenes to make predictions about potential suspects.

This technology, called forensic “DNA phenotyping”, can reveal a surprising and growing amount of highly personal information from the traces of DNA we all leave behind wherever we go – including information about our gender, ancestry and appearance.

Queensland police have already used versions of this approach to identify a suspect and identify remains. Forensic services in Queensland and New South Wales have also investigated the use of predictive DNA.

This technology can reveal much more about a suspect than previous DNA forensic methods. But how does it work? What are the ethical issues? And what approaches are other countries taking around the world?

How does it work?

AFP plans to implement forensic DNA phenotyping based on an underlying technology called “massive parallel sequencing

Our genetic information is encoded in our DNA as long strands of four different base molecules, and sequencing is the process of “reading” the sequence of these bases.

Older DNA sequencing machines could only read one bit of DNA at a time, but current “massively parallel” machines can read more than six trillion DNA bases in a single run. This creates new opportunities for DNA analysis.

DNA forensics used to rely on a system that matched samples with them in a criminal DNA database and did not reveal much beyond identity. Predictive DNA forensics can, however, reveal things like physical appearance, gender and ancestry – whether people are in a database or not.

This makes it useful in cases of missing persons and the investigation of unidentified remains. This method can also be used in criminal cases, mostly to exclude persons of interest.

AFP plans to predict gender, “biogeographical ancestry”, eye color and in the coming months hair color. Over the next decade, they aim to include characteristics such as age, body mass index and height and even finer predictions for face measurements such as eye distance, eye, nose and ear shape, lip fullness and cheek structure.

Are there any issues or ethical concerns?

DNA can reveal very sensitive information about us. In addition to ancestry and externally visible characteristics, we can predict many other things, including aspects of both physical and mental health.

It will be important to set clear boundaries around what can and cannot be predicted in these tests – and when and how they will be used. Despite some progress towards an assessment of the impact on privacy, Australian forensic legislation does not currently provide for any comprehensive regulation of forensic DNA phenotyping.

The very sensitive nature of DNA data and the difficulty of ever making them anonymous create significant concerns about privacy.

According to a 2020 government survey on public attitudes to privacy, most Australians are uncomfortable with the idea of ​​having their DNA data collected.

Using DNA for forensic medicine can also reduce public confidence in the use of genomics for medical and other purposes.

AFP’s planned test includes the prediction of biogeographical origins. Even when not explicitly tested, DNA data are closely linked to our ancestry.

One of the biggest risks of any DNA data is aggravating or creating racial imbalances. This is especially the case in law enforcement, where specific groups of people may be targeted or stigmatized based on pre-existing inequalities.

In Australia, original legal experts report that not enough is being done to completely eradicate racism and unintentional bias in the police force. Concerns have been raised about other types of potential institutional racial profiling. A recent analysis from ANU also showed that 3 out of 4 people had an implicit negative or unconscious bias towards native Australians.

Careful consideration, consultation and clear regulatory safeguards must be in place to ensure that these methods are used only to exclude persons of interest instead of including or targeting specific groups.

DNA data also has inherent risks around misinterpretation. People rely heavily on DNA evidence, although it often yields probable findings that can be difficult to interpret.

What are other countries doing?

Predictive DNA forensics is a relatively new field, and countries across Europe have taken different approaches to how and when to use it. A 2019 survey across 24 European countries showed that ten had allowed the use of this technology for practical purposes, seven had not allowed it, and a further seven had not yet made a clear decision on its use.

DNA-based prediction is used in some European countries and banned in others.  Adapted from Schneider, Prainsack & Kayser / Dtsch Arztebl Int.