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A high-performance multilane microdevice system designed for the DNA forensics laboratory.

Abstract

We report preliminary testing of "GeneTrack", an instrument designed for the specific application of multiplexed short tandem repeat (STR) DNA analysis. The system supports a glass microdevice with 16 lanes of 20 cm effective length and double-T cross injectors. A high-speed galvanometer-scanned four-color detector was specially designed to accommodate the high elution rates on the microdevice. All aspects of the system were carefully matched to practical crime lab requirements for rapid reproducible analysis of crime-scene DNA evidence in conjunction with the United States DNA database (CODIS). Statistically significant studies demonstrate that an absolute, three-sigma, peak accuracy of 0.4-0.9 base pair (bp) can be achieved for the CODIS 13-locus multiplex, utilizing a single channel per sample. Only 0.5 microL of PCR product is needed per lane, a significant reduction in the consumption of costly chemicals in comparison to commercial capillary machines. The instrument is also designed to address problems in temperature-dependent decalibration and environmental sensitivity, which are weaknesses of the commercial capillary machines for the forensics application.

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BibTeXRIS

Nils Goedecke, Brian McKenna, Sameh El-Difrawy, Loucinda Carey, Paul Matsudaira, Daniel Ehrlich. 2004. A high-performance multilane microdevice system designed for the DNA forensics laboratory.. https://doi.org/10.1002/elps.200305897

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