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A developmental validation was performed to demonstrate reliability, reproducibility and robustness of the ANDE System with the FlexPlex assay, including an integrated Expert System, across a number of laboratories and buccal sample variations. Previously, the related DNAscan™/ANDE 4C Rapid DNA System using the PowerPlex ® 16 assay and integrated Expert System Software received NDIS approval in March 2016. The enhanced ANDE instrument, referred to as ANDE 6C, and the accompanying 6-dye, 27-locus STR assay, referred to as FlexPlex, have been developed to be compatible with all widely used global loci, including the expanded set of the CODIS core 20 loci. Six forensic and research laboratories participated in the FlexPlex Rapid DNA developmental validation experiments, testing a total of 2045 swabs, including those obtained from 1387 unique individuals. The goal of this extensive and comprehensive validation was to thoroughly evaluate and document the ANDE System and its internal Expert System to reliably genotype reference buccal swab samples in a manner compliant with the FBI's Quality Assurance Standards and the NDIS Operational Procedures. The ANDE System, including automated Expert System analysis, generated reproducible and concordant results for buccal swabs when testing various instruments at different laboratories by a number of different operators. When testing a number of non-human DNAs, including oral bacteria, the ANDE System and FlexPlex assay demonstrated limited cross-reactivity. Potential PCR inhibitors were evaluated as part of the validation and no inhibition was detected. Reproducible and concordant profiles were generated from buccal swab samples collected with a limit of detection appropriate for buccal swab collections from arrestees. The precision and resolution of the System met industry standards for detection of microvariants and single base resolution. The integrated Expert System appropriately demonstrated the ability to correctly pass or fail profiles for CODIS upload without human review. During this comprehensive developmental validation, the ANDE System successfully interpreted over 2000 samples tested with over 99.99% concordant alleles. The data package described herein led to the ANDE System with the FlexPlex assay receiving NDIS approval in June 2018., (Copyright © 2019 The Authors. Published by Elsevier B.V. All rights reserved.)

Since the implementation of forensic DNA typing in labs more than 20 years ago, the analysis procedures and data interpretation have always been conducted in a laboratory by highly trained and qualified scientific personnel. Rapid DNA technology has the potential to expand testing capabilities within forensic laboratories and to allow forensic STR analysis to be performed outside the physical boundaries of the traditional laboratory. The developmental validation of the DNAscan/ANDE Rapid DNA Analysis System was completed using a BioChipSet™ Cassette consumable designed for high DNA content samples, such as single source buccal swabs. A total of eight laboratories participated in the testing which totaled over 2300 swabs, and included nearly 1400 unique individuals. The goal of this extensive study was to obtain, document, analyze, and assess DNAscan and its internal Expert System to reliably genotype reference samples in a manner compliant with the FBI's Quality Assurance Standards (QAS) and the NDIS Operational Procedures. The DNAscan System provided high quality, concordant results for reference buccal swabs, including automated data analysis with an integrated Expert System. Seven external laboratories and NetBio, the developer of the technology, participated in the validation testing demonstrating the reproducibility and reliability of the system and its successful use in a variety of settings by numerous operators. The DNAscan System demonstrated limited cross reactivity with other species, was resilient in the presence of numerous inhibitors, and provided reproducible results for both buccal and purified DNA samples with sensitivity at a level appropriate for buccal swabs. The precision and resolution of the system met industry standards for detection of micro-variants and displayed single base resolution. PCR-based studies provided confidence that the system was robust and that the amplification reaction had been optimized to provide high quality results. The DNAscan integrated Expert System was examined as part of the Developmental Validation and successfully interpreted the over 2000 samples tested with over 99.998% concordant alleles. The system appropriately flagged samples for human review and failed both mixed samples and samples with insufficient genetic information. These results demonstrated the integrated Expert System makes correct allele calls without human intervention., (Copyright © 2016 The Authors. Published by Elsevier Ireland Ltd.. All rights reserved.)

Quantification of the total amount of human DNA isolated from a forensic evidence item is crucial for DNA normalization prior to short tandem repeat (STR) DNA analysis and a federal quality assurance standard requirement. Previous commercial quantification methods determine the total human DNA and total human male DNA concentrations, but provide limited information about the condition of the DNA sample. The PowerQuant(®) System includes targets for quantification of total human and total human male DNA as well as targets for evaluating whether the human DNA is degraded and/or PCR inhibitors are present in the sample. A developmental validation of the PowerQuant(®) System was completed, following SWGDAM Validation Guidelines, to evaluate the assay's specificity, sensitivity, precision and accuracy, as well as the ability to detect degraded DNA or PCR inhibitors. In addition to the total human DNA and total human male DNA concentrations in a sample, data from the degradation target and internal PCR control (IPC) provide a forensic DNA analyst meaningful information about the quality of the isolated human DNA and the presence of PCR inhibitors in the sample that can be used to determine the most effective workflow and assist downstream interpretation., (Copyright © 2016 The Author(s). Published by Elsevier Ireland Ltd.. All rights reserved.)

Multiplex PCR with fluorescently labeled primers has been an essential method for the amplification of short tandem repeats used in human identify testing. Within the STR workflow of extraction, quantitation, amplification, separation, and detection, multiplex PCR is commonly identified as the bottleneck in the process. The time requirement of up to three hours to complete 28-30 cycles of multiplex PCR for STR genotyping is the greatest amount of time required for a single step within the process. The historical use of commercially available thermal cyclers and heat stable polymerases may have given the impression that large multiplex will always require long PCR cycling times to ensure that all of the varying sized targets (typically 100-400bp) can be amplified in a balanced manner throughout the multiplex. However, with the advent of improved polymerases and faster thermal cyclers the time required for the amplification of large STR multiplexes is no longer on the order of three hours, but as little as 14min. Faster amplification times can be performed while retaining the balance and integrity of large multiplex PCRs by implementation of alternate polymerases and thermal cyclers. With the reduction in PCR cycling times there has also been an impact on the development of integrated and microfluidics devices which employ the use of reduced or rapid thermal cycling protocols as part of their integration. Similarly, PCR inhibitor resistant polymerases can also reduce overall STR processing times for reference samples by eliminating the need for DNA extraction and purification that is additionally implemented within the development of integrated DNA typing devices., (Published by Elsevier Ireland Ltd.)