Developmental validation of a 6-dye STR kit with 27 loci
The EX27 System is a 6-dye (i.e., FAM, HEX, TAMAR, ROX, VIG, and SIZ-500) kit that combines the 24 autosomal STR loci (i.e., D3S1358, D13S317, D7S820, D16S539, D1S1656, Penta E, TPOX, TH01, D2S1338, CSF1PO, Penta D, D10S1248, D19S433, vWA, D21S11, D18S51, D6S1043, D8S1179, D5S818, D12S391, FGA, D22S1045, D2S441, SE33) with a Y-STR locus (DYS391), an Indel site (YIndel) and Amelogenin, which is designed to amplify DNA from extracts as well as direct amplification from substrates. The new system contains most of the widely used autosomal STR loci around the world and is sensitive to the male component in mixtures and is more accurate in gender determination owing to the DYS391 and YIndel.
To demonstrate the suitability for personal identification and parentage testing, the system was validated for sensitivity of detection, species specificity, inhibitor tolerance, DNA mixtures, reproducibility study, and concordance studies based on the SWGDAM developmental validation guidelines. In view of the results, the EX27 System is a robust and reliable amplification kit which can be used for human identification testing.
KeywordsForensic Science Short tandem repeat (STR) 6-dye multiplexing system
The authors would like to thank the donors who generously provide samples for this validation study and thank support from the Ministry of Public Security application innovation projects (NO. 2011YYCXGDST076) as well as Science and Technology project of Guangdong Province (NO. 2010A060801001).
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