Concordance testing between Powerplex ESI 16 Fast System and VeriFiler Express.

DNA profiles generated by different STR kits may show different alleles for identical amplified loci. This well‐known phenomenon affects the smooth transition of data generated by new STR kits to a database or casework laboratory or cross‐laboratory comparison of STR profiles. As in other DNA databases throughout the world, it has become clear that the number of the analyzed loci should be expanded for a variety of reasons, such as partial profiles resulting from low copy‐number DNA template or degraded samples, working with mixtures or when prevalence of familial inbreeding. In the course of introducing a new STR kit, VeriFiler™ Express (Applied Biosystems, Foster City, CA, USA), we compared genotyping data of 1568 samples amplified by the VeriFiler™ Express with the data generated on the same samples by the Powerplex™ ESI FAST (Promega, Madison WI, USA) kit. Discordance was noted in 20 samples (1.27%), 14 (0.89%) of them showing allele dropout mismatch and six (0.38%) showing an additional fixed‐size third allele. These rates are well above the reported rates of 0.4% for this kit. Since correct genotyping and accurate consistent allele assignment is of paramount importance, it seems timely to recommend for DNA laboratories and genetic‐match search systems to take these possible inconsistencies into account. [ABSTRACT FROM AUTHOR]