Developmental validation study of a 32-plex STR direct amplification system for forensic reference samples

The STRtyper-32G PCR Amplification Kit is a 6-dye multiplex system that combines the 30 autosomal STR loci with an Indel site (Y_Indel) and the sex-determinant locus Amelogenin. In addition to more loci, Master Mix has been optimized to amplify DNA on different substrates. The autosomal STR loci contained in this novel system meet the compatibility of requirements for databasing. In this study, the developmental validation study of the STRtyper-32G Kit followed the guidelines of SWGDAM (Scientific Working Group on DNA Analysis Methods), including PCR-based studies, species specificity, inhibitors, sensitivity, precision, repeatability, stutter, DNA mixtures, concordance studies, and population genetics studies. The validation results indicate that the new multiplex system is a robust tool for forensic database applications.