Automating a combined composite–consensus method to generate DNA profiles from low and high template mixture samples

• Published in: Forensic science international : genetics Vol. 6; no. 5; pp. 588 - 593
• Main Authors: Bekaert, Bram, Van Geystelen, Anneleen, Vanderheyden, Nancy, Larmuseau, Maarten H.D, Decorte, Ronny
• Format: Journal Article
• Language: English
• Published: Netherlands 01.09.2012
• Subjects: Alleles; Automation; DNA - genetics; Humans; Pathology; Polymerase Chain Reaction; Reproducibility of Results; Mixture sample; Replicate PCR; Combined composite–consensus profile
• ISSN: 1872-4973; 1878-0326
• DOI: 10.1016/j.fsigen.2012.02.001

Abstract We present an automated method to generate DNA profiles from replicate PCRs by combining advantages of the composite and consensus method by a system of brackets in which an allelic balance threshold is used as a variable to separate DNA-profiles of major from minor donors. Through the analysis of artificial low (125 pg) and high (250 pg) template three-person mixtures with low (1:1.5:3) and high (1:5:10) donor ratios we demonstrate the usefulness of a tool to determine the optimal allelic balance threshold within a locus. The automated extraction of dominant profiles saves considerable amounts of time when producing composite–consensus profiles. Drop-in/drop-out rates are produced and a comparison is made with an alternative open source script to evaluate the dominant profiles generated. By introducing this script into the forensic community we hope to increase awareness of much needed collaborative efforts with bioinformaticians and statisticians to develop forensic open source software scripts.