Developmental validation of the EX16+22Y system
The EX16+22Y system is a polymerase chain reaction (PCR) based amplification kit that enables typing of 15 autosomal short tandem repeat (STR) loci (i.e. D3S1358, D13S317, D7S820, D16S539, TPOX, TH01, D2S1338, CSF1PO, D19S433, vWA, D18S51, D21S11, D8S1179, D5S818, and FGA) and 22 widely used Y chromosome STR (Y STR) loci (DYS391, DYS527a/b, DYS635, DYS458, DYS456, DYS385a/b, DYS438, DYS448, DYS437, DYS19, DYS576, DYS533, DYS393, DYS389I/II, DYS439, DYS392, Y_GATA_H4, DYS390, and DYS481) which contains 20 core Y STR recommended by the Ministry of Public Security and amelogenin. This multiplex system was designed for the simultaneous analysis of amelogenin Y allele mutation, single source searches, kinship (including familial searching) mixture profiles, international data sharing, and other forensic applications. In this study, the multiplex system was validated for sensitivity of detection, species specificity, DNA mixtures, stability, sizing precision, stutter, reproducibility, and PCR based conditions according to the Scientific Working Group on DNA Analysis Methods developmental validation guidelines and Chinese criteria for the human fluorescent STR multiplex PCR reagent. The results show that the EX16+22Y system is a robust and reliable amplification kit which can be used for human identification testing.