Pennsylvania prosecutors use TrueAllele in homicide guilty plea

Back to Publications

Validation study of the TrueAllele® automated data review system

Kadash, K., Kozlowski, B.E., Biega, L.A., and Duceman, B.W. Validation study of the TrueAllele® automated data review system. Journal of Forensic Sciences, 49(4):1-8, 2004.


Downloads

Journal of Forensic Sciences


Abstract

The New York State Convicted Offender DNA Databank is the first U.S. lab to complete an internal validation of the TrueAllele® expert data review system. TrueAllele is designed to assess short tandem repeat (STR) DNA data based on several key features such as peak height, shape, area, and position relative to a standard ladder and use this information to make accurate allele calls. The software then prioritizes the allele calls based on several user-defined rules. As a result, the user need only review low-quality data. The validation of this system consisted of an extensive optimization phase and a large concordance phase. During optimization, the rule settings were tailored to minimize the amount of high-quality data viewed by the user. In the concordance phase, a large dataset was typed in parallel with the ABI software Gene Scan and Genotyper (manual review) and TrueAllele (automated review) for comparison of allele calls and sample state assignment. Only one significant difference was discovered out of 2048 samples in the concordance study. In this case, TrueAllele revealed a spike in the profile that was interpreted as a DNA peak by the analyst in Genotyper. TrueAllele was designed to focus the review on poor data and to eliminate the need for complete reanalysis technical review. This validation project proved TrueAllele to be dependable for use at the NYS Convicted Offender DNA Databank.