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A 26plex Autosomal STR Assay to Aid Human Identity Testing

NCJ Number
Journal of Forensic Sciences Volume: 54 Issue: 5 Dated: 2009 Pages: 1008-1015
Date Published
September 2009
8 pages

This paper presents the authors’ development and testing of a 26plex that may benefit the forensic science community by providing reference sample testing and complex relationship evaluation.


The authors of this paper describe their successful development of a short tandem repeat multiplex assay with 25 autosomal loci plus the sex-typing locus amelogenin, for a total of 26 amplified products in a single reaction. They designed primers for the loci so that all of the amplicons present were distributed from 65 base pairs (bp) to less than 400 bp within a five-dye chemistry design with the fifth dye reserved for the sizing standard. They developed a multiplex design strategy to overcome challenges encountered in creating this assay and tested the limits of the multiplex, resulting in the successful amplification of a wide range of genomic DNA sample concentrations from two ng to as low as 100 pg with 30 cycles of PCR. The authors suggest that the 26plex has the potential to benefit the forensic community for reference sample testing and complex relationship evaluation. Publisher Abstract Provided

Date Published: September 1, 2009