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Internal Validation of the Applied Biosystems® GlobalFilerTM Express PCR Amplification Kit

NCJ Number
Shanna Saunders; Kyra Groeblinghoff ; Season Seferyn ; Pamela Staton
Date Published
1 page

This brief report provides an overview of the internal validation of the Applied Biosystems® GlobalFiler™ Express DNA Amplification Kit, including materials and methods used, validation studies performed, and conclusions.


This brief report describes the internal validation process of the Applied Biosystems® GlobalFiler™ Express DNA Amplification Kit, which is a novel kit to the St. Louis County Police Crime Laboratory, in fulfillment of the FBI (Federal Bureau of Investigation) Quality Assurance Standards requiring any novel PCR (polymerase chain reaction) amplification chemistry to be validated in order to ensure that reliable data is being produced. The Applied Biosystems® GlobalFiler™ Express DNA Amplification Kit utilizes advancements in buffers and amplification kits that allow extraction and quantitation steps to be modified or removed, decreasing costs while increasing time savings, and allow those resources to be redirected to casework. The authors present a brief description of the materials and methods of the studies to validate this kit; they list the validation studies performed, with special attention given to the sensitivity/non-probative sample types, injection time, and Analytical Threshold (AT) and Stochastic Threshold (ST). The authors also discuss the precision and reproducibility of the validation performed, noting that a both a Precision Study and a Reproducibility Study was completed to ensure that sizing within an injection was consistent, and twenty four allelic ladders were run and base pair size was analyzed for precision as well as reproducibility. The authors also provide information on stutter ratios (SR). Conclusions suggest that the GlobalFiler™ Express DNA Amplification Kit on the 3500 Genetic Analyzer is recommended for use with future single-source samples to increase throughput for the St. Louis County Police Crime laboratory. The authors also note that the reliability and reproducibility of the incorporation of this chemistry and platform are based on the settings and recommendations determined from the validation studies.