At the FBI Crime Lab in Quantico, Va., experts are finding new and better uses for what many people see as a forensic sure thing – DNA, reports National Public Radio. Expectations are rising because the science is getting better. Not long ago, forensic experts needed a sample about the size of a nickel for processing. Now it just needs to be the size of a pin prick. That means that cases unsolvable a decade ago are now ripe for reopening. At the FBI’s nuclear DNA lab, a new machine allows a robot to process DNA samples at an exponentially higher rate than humans ever could. This is where the FBI is processing punch cards with DNA samples from federal offenders. The FBI is trying to get a roster of prior criminals into a national database that will not only help law enforcement solve new crimes, but potentially old ones, too.
Jennifer Luttman, who runs the convicted offender program at the lab, says the FBI still uses people to find the DNA at a crime scene, but steps that come after that are easily automated. “We still use humans to look for the stains, to test for blood, to test for semen, to cut out the stains,” she said. “Only a human can do that because they need to see how much is there and that’s all based on experience.” Down the hall, other FBI scientists are trying to tug clues from a different kind of DNA, called Mitochondrial DNA. Alice Eisenberg, head of the FBI’s Mitochondrial DNA Analysis lab, says cold cases are the meat and potatoes of her unit. Typically, technicians deal with bone and hair samples that sat on evidence room shelves for years. The newest wrinkle involves a mass spectrometer, in essence a glorified scale that weighs individual molecules.