Australian Federal Police (AFP) investigators are taking the time-tested sketch artist to a completely new level after validating the use of DNA sequencing technology to predict the gender, ethnicity and eye colour of persons of interest using DNA left at a crime scene.
Known as massively parallel sequencing (MPS), the technology – also called next-generation sequencing (NGS) – uses a range of laboratory techniques to analyse DNA nucleotide strands with much greater resolution than was previously possible.
Large-scale processing enables the extraction of detailed DNA sequences from a forensic sample – for example, a strand of hair, drop of bodily fluid or skin scraping – and zeroes in on key parts of the genetic code contained within them.
Given that traits such as eye and hair colour are genetically linked, the technique – which the AFP has called “more informative than traditional DNA profiling” – has created an opportunity for investigators to build profiles of persons of interest even where there were no eyewitnesses to a crime scene.
Samples are also being compared with a reference library of “three ancient human population groups”, the AFP said in announcing its use of the technology, which will also allow investigators to predict the ethnicity of the person from whom a sample of interest came.
The AFP expects to be able to determine a suspect’s hair colour soon, while future refinements will allow investigators to determine a range of facial metrics including eye, nose, and ear shape; lip fullness; cheek structure; and the distance between the eyes.
DNA as a sketch artist
UK authorities have previously recommended that the adoption of MPS be guided by four ethical controls, including transparency around use of “phenotypic and ancestral markers”; use of probabilities to identify levels of analytic certainty; continuous-improvement obligations on equipment makers; and clarity around when and why MPS would be used.
The AFP, for its part, argues that careful testing of MPS technology has helped it validate the accuracy of the technique well enough to substantiate its use in forensic analysis.
The technique is already being used to develop physical descriptions of people whose remains are found but cannot be physically identified – such as a NSW Health Pathology project using MPS to compare human remains to profiles of known missing persons.
Another recently announced project, headed by the Department of Defence and Queensland University of Technology’s Centre for Genomics and Personalised Health, is using NGS to build a database called Biobank using DNA samples from the descendants of around 500 missing soldiers.
Comparing familial DNA with samples from unidentifiable remains will, investigators believe, allow those remains to be profiled by using genetic markers to determine their likely hair, eye, and skin colour.
“This will aid Defence to target identification to fewer possible unaccounted soldiers,” said project lead Distinguished Professor Lyn Griffiths, “and significantly reduce investigation and identification time.”
Yet despite its potential utility, the technique is also raising concerns including worries that criminals could plant DNA to throw off investigators – or that it could fuel a rise in wrongful convictions and racial profiling, in which police focus their investigations based solely on suspects’ race or appearance.
Australians are protective of their biometric information, with a recent Office of the Australian Information Commissioner (OAIC) privacy survey noting that 66 per cent of respondents are “generally reluctant to provide biometric information” to businesses or government bodies.
Just 35 per cent of respondents said they were comfortable with a government organisation using biometrics and “smart technologies” to deliver services.
And while 58 per cent of respondents were OK with law-enforcement bodies using facial recognition and video surveillance to identify criminal suspects, just 23 per cent said they were comfortable with collection of their DNA information.
Mindful of the controversy over the use of such profiling techniques, the AFP noted that it “is mindful of maintaining public trust and confidence in the use of new bio-technology, and has implemented processes to minimise privacy impacts and to safeguard any genetic information.”