Two-year review of firearm-related DNA casework evidence: A triage process to improve quality and efficiency.

A two-year casework review of 617 firearm-related submissions representing 119 cases has provided a DNA testing triage template for prioritizing and processing touch evidence associated with firearms and firearm accessories. The evidence consisted of swabbings from various locations of a firearm or a firearm-related item, and each submission was assigned to one of the following descriptive groups: Body, Magazine, Trigger Area, Rifles, Gun Accessories, Barrel, Miscellaneous, or Revolvers. Ultimately, there were 543 submissions analyzed from DNA extraction through electrophoresis, and interpretable profiles evaluated to determine eligibility for entry into The Combined DNA Index System (CODIS).

Developmental validation of the PowerPlex 16 HS System: an improved 16-locus fluorescent STR multiplex.

STR multiplexes remain the cornerstone of genotyping forensic samples. The PowerPlex 16 HS System contains the core CODIS loci: D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, CSF1PO, FGA, TH01, TPOX, and vWA. Additional loci amplified in the multiplex reaction are the sex-determinant locus, amelogenin, and two pentanucleotide STR loci, Penta D and Penta E.

A forensic laboratory tests the Berkeley microfabricated capillary array electrophoresis device.

Miniaturization of capillary electrophoresis onto a microchip for forensic short tandem repeat analysis is the initial step in the process of producing a fully integrated and automated analysis system. A prototype of the Berkeley microfabricated capillary array electrophoresis device was installed at the Virginia Department of Forensic Science for testing. Instrument performance was verified by PowerPlex 16 System profiling of single source, sensitivity series, mixture, and casework samples.

Rapid and high-throughput forensic short tandem repeat typing using a 96-lane microfabricated capillary array electrophoresis microdevice.

A 96-channel microfabricated capillary array electrophoresis (muCAE) device was evaluated for forensic short tandem repeat (STR) typing using PowerPlex 16 and AmpFlSTR Profiler Plus multiplex PCR systems. The high-throughput muCAE system produced high-speed <30-min parallel sample separations with single-base resolution. Forty-eight previously analyzed single-source samples were accurately typed, as confirmed on an ABI Prism 310 and/or the Hitachi FMBIO II.

Improving efficiency of a small forensic DNA laboratory: validation of robotic assays and evaluation of microcapillary array device.

Aim: To present validation studies performed for the implementation of existing and new technologies to increase the efficiency in the forensic DNA Section of the Palm Beach County Sheriff's Office (PBSO) Crime Laboratory.

Methods: Using federally funded grants, internal support, and an external Process Mapping Team, the PBSO collaborated with forensic vendors, universities, and other forensic laboratories to enhance DNA testing procedures, including validation of the DNA IQ magnetic bead extraction system, robotic DNA extraction using the BioMek2000, the ABI7000 Sequence Detection System, and is currently evaluating a micro Capillary Array Electrophoresis device.

Results: The PBSO successfully validated and implemented both manual and automated Promega DNA IQ magnetic bead extractions system, which have increased DNA profile results from samples with low DNA template concentrations.