Forensics
by Joanie Brocato
Electronic DNA Sample Processing Preserves Evidence Integrity in the Forensics Laboratory
T
en years ago, most forensics laboratories tested and analyzed a manageable number of samples. Most of those labs also did not anticipate the current surge of evidence and what would be required to keep up with it. A large number of new cases come from law enforcement agencies, and in many instances contain DNA evidence. It is critical that this evidence be tested as quickly as pos- sible to provide real-time investigative support by way of providing matches to known suspects or utilizing investigative leads that are developed through the Combined DNA Index System (CODIS), which contain known DNA profiles of convicted offenders, arrestees, un- identified human remains, missing persons and relatives of missing persons. Because laboratories cannot immediately work on every case they receive, testing must be prioritized.
Strained operating budgets and high staff turnover put further pressure on productivity. Fortunately, many of these challenges can be mitigated by automating those laboratory operations that can be automated and by employing electronic DNA sample management systems. Without these aids, a limited number of samples could be processed. “We would see more errors and more variations in quality,” noted Brian Hoey, labora- tory manager and DNA technical leader at the Missouri State Highway Patrol. “We wouldn’t be able to have a high throughput with built-in quality checks, and would probably be at a greater disadvantage to reduce the backlogs.”
Backlogs could be reduced by combining integrated LIMS and DNA sample management solutions and more staffing, according to Jay Henry, past president of the American Society of Crime Lab Directors (ASCLD). “Relevant stakeholders have to realize that we are only pushing the constraint of backlogs from the interface (evidence intake) to the lab (via automation) and now to the analyst, who must evaluate the data and write and review reports,” he said. “The bottom line is that you will need people to evaluate the information that comes from these samples. So, in essence, it’s a combined solution of working smarter (what we are testing), and working more efficiently (using robotics and sample management software).”
Automated DNA sample management Many automated and electronic systems are available to the laboratory
for sample processing. The following is a list of representative hardware and software products and a discussion of how these are being used in various forensics laboratories.
Robotics • Tecan Freedom EVO robotic liquid handling workstation for processing samples (Tecan, Morrisville, N.C.)
• AutoLys workstation—automates the entire sample lysis and lysate recovery process (Hamilton Robotics, Reno, Nev.)
• Maxell16 (Promega Corp., Madison, Wis.), iPrep (Invitrogen, Life Technologies, Grand Island, N.Y.), QIAamp kits (QIAGEN, Valencia, Calif.) and EZ1 extraction robots (QIAGEN)—designed for nucleic acid and genomic DNA extraction
• JANUS automated DNA extraction and liquid handling workstation (PerkinElmer, Waltham, Mass.).
DNA sample management software • LIMS-plus DNA is a standalone DNA application for automating forensic sample processing for casework and databanks. It helps automate delivery of DNA profiles to local, state and national databanks; provides integration across all systems in the forensics laboratory, particularly instrument data and LIMS data sharing; and tracks all methods, reagents, batches and instruments at the sample level and for each examiner (JusticeTrax, Mesa, Ariz.)
• STACS-CW Family of Solutions DNA l software tracks DNA samples, users, consumables, instruments, cases, exhibits, profiles and results. Reports can be generated, and users can create and process batches and add or remove a set of samples with controls to/from a batch at any analytical step as the need arises (STACS DNA, Fairfax, Vir.)
• Crime Fighter BEAST (bar-coded evidence analysis statistical tracking) is a DNA module built into the Crime Fighter BEAST LIMS. It interfaces with instruments and robots. Onscreen worksheets are instantly converted to plate setup files exported directly to the laboratory’s instruments for quantitation, amplification and analysis protocols (Porter Lee Corp., Schaumberg, Ill.).
Automated workflow and DNA sample processing In 2010, in an effort to make the DNA sample management process as
efficient as possible, the Louisiana State Police Crime Laboratory (LSPCL, Baton Rouge, La.) engaged in a Lean Six Sigma Training Project, dur- ing which experts in the DNA field studied the unit’s workflow. While the processes were deemed efficient, the laboratory was lacking an electronic DNA sample management solution with the ability to modify
AMERICAN LABORATORY • 30 • AUGUST 2015
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