In both the United States and Canada, there are nearly half a million sexual assault cases reported every year — with countless more going unreported.
For researchers at the University of Toronto, this was the basis of their latest study.
“For this research, we read reports and surveys that asked victims why they weren’t reporting assaults,” Mohamed Elsayed, a biomedical engineering researcher at the university said.
“And the most common answer was that they didn’t have confidence in the justice system — and that lack of confidence was partly because of how long the process takes.”
It’s true; the “rape kit backlog” has long been an issue for survivors and anti-violence advocates.
According to the Rape, Abuse & Incest National Network, in the past decade, cities and states across the U.S. have found thousands of untested rape kits — DNA evidence that was collected by law enforcement or during sexual assault forensic exams.
Many of the samples had been sent to crime labs but never tested. Other samples had never even gone to the crime labs in the first place.
RAINN calls this the “hidden backlog.”
While changes must be made among law enforcement systems to accurately and quickly address sexual assault cases, improving DNA collection is also a vital element in helping survivors.
So that’s what Elsayed and his co-authors — chemistry master’s student Leticia Bodo and biomedical engineering professor Aaron Wheeler — set out to research.
Their findings, just published in the journal Advanced Science, lay out a new technique for analyzing DNA evidence that could radically streamline the forensics pipeline.
A faster way to analyze DNA
Right now, processing evidence in sexual assault cases is highly technical and takes many steps, first collecting evidence from a victim of sexual assault, and then sending that evidence to a lab, where a technician isolates the assailant’s DNA from the victim’s.
From there, the analysis of the assailant’s DNA can potentially be used to identify a suspect — though the process can take days or weeks, according to the researchers. Much of this time is spent transporting evidence to the lab, but delays are also due to a large queue of cases requiring analysis.
“Faster and more accessible DNA analysis may one day enable all sexual assault evidence to be tested (quickly), without having to go through the many hurdles that are currently in the system,” Elsayed told Interesting Engineering.
To speed things along, the University of Toronto researchers focused on the first step: isolating the DNA of two individuals from a single sample. At this moment in time, there is no automated way to do this; only skilled lab technicians can manually separate two samples.
Elsayed’s team, however, used digital microfluidics to conduct a differential digestion technique (the process of distinguishing between sperm cells and non-sperm cells).
Essentially, digital microfluidics is an advanced technology that can manipulate a fluid into tiny droplets or substrates on a series of electrodes to more efficiently perform complex laboratory procedures.
The researchers were inspired by the use of digital microfluidics to automate processes in genome sequencing — even in remote settings like refugee camps.
“The programmability inherent to digital microfluidics led us to hypothesize that it could be well suited to automate differential digestion,” the researchers wrote in their study.
And they were right; by processing a fluid sample through this method, it reduced the manual steps of a differential digestion technique, which, for survivors desperate for answers, could be game-changing.
Using current methods, technicians take 13 steps to isolate an assailant’s DNA from a sample — this approach could reduce that to just five.
“Also, because microfluidic processes tend to be faster, we expect that one of the eventual benefits will be shortening the overall time needed,” Elsayed explained in a statement for the university.
Due to the ease of this technology, the analysis process could be contained to a hospital, eliminating delays caused by transportation and lab wait times.
Elsayed said the process would not require extensive training for hospital staff, as prior studies have depicted the ease of training hospital teams in testing microfluidic blood samples.
Right now, this technique takes about 45 minutes to complete and is compatible with Rapid DNA Analysis, which is what experts already use to identify an individual from their DNA.
The researchers hope to integrate the two technologies, making the process even more streamlined. Though there will need to be further research to make this technique operational and commercially viable, they are optimistic.
“Our plan is to develop an instrument that will do in five minutes what currently takes 45, and to run many more samples than previously,” Elsayed said.
“Once we do that, the next step would be to introduce the technology to forensic labs and hospitals. It will take years, but the potential is very exciting.”
Header image courtesy of Wheeler Microfluidics Laboratory/University of Toronto
