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Next Rung: Validation of Modified Allelic Ladders From Applied Biosystems

NCJ Number
Canadian Society of Forensic Science Journal Volume: 41 Issue: 2 Dated: June 2008 Pages: 61-71
C. Carroll; P. Philion
Date Published
June 2008
11 pages
This paper describes the internal validation study conducted by the National DNA Data Bank (NDDB) and the Royal Canadian Mounted Police (RCMP)-Biology Services Directorate (BSD).
Results show that the modified allelic ladders meet the stringent requirement for forensic DNA testing, and are suitable for use with both the NDDB and BSD capillary electrophoresis (CE) protocols. Although the internal validation study conducted by the NDDB and BSD was not an extensive one due to the fact that it involved a reagent modification rather than the implementation of a new methodology, it sufficiently demonstrated the robustness, reliability, and reproducibility of the modified Profiler Plus ™ and COfiler ™ allelic ladders as practiced by these forensic and database laboratories. Results demonstrated that the modified allelic ladders have the same sizing precision and genotyping capabilities as the previous allelic ladders and that instrument precision has not changed. As well, the sizing precision results are similar to those obtained from the performance verification studies carried out by the manufacturer. Although better allele balance across all loci with the modified Profiler Plus ™ and COfiler ™ allelic ladders was noted, no significant increase in peak heights was observed. The observed peak heights still met the minimum performance requirement for the quality control testing of both allelic ladders. Nine samples were used in this validation study. Figures, tables and references