In California’s Alameda County forensics laboratory where rape kits are processed, robots have reduced the time needed to test kits — the sets of evidence collected from a victim after a sexual assault — by processing dozens of DNA samples at once, reports Vocativ. The innovation is vital, as the U.S. reckons with a backlog of hundreds of thousands of untested rape kits. It’s a piece of software, not hardware, that is being heralded as the future of rape kit testing. It’s algorithms, not robots, that could revolutionize this beleaguered area of DNA testing, and forensics in general.
“It’s kind of what everyone is talking about, where everyone is going,” said Kristi Lanzisera of the Alameda County Sheriff’s forensic biology unit, after showing off an array of robotics. The technology is called probabilistic genotyping, and it greatly simplifies the process of identifying an offender’s genotype from a DNA sample. Rape kits often contain samples with both the victim’s DNA and that of at least one perpetrator. These are known as mixtures and they’re incredibly difficult to analyze. In identifying a genotype, analysts typically compare variations, or alleles, on 13 points in the DNA. But when there are multiple people’s DNA involved in a sample, it can be difficult to tell which alleles belong together or, put another way, to the same person. Probabilistic genotyping software performs complex mathematical computations much faster and with greater accuracy than a human can of the individual genotypes in a mixture. What that means is that it might take less time to test rape kits. Mind-shatteringly difficult mathematical calculations that might have taken several hours can now be done in minutes..