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The PowerPlex Fusion 6C system is a six-dye STR multiplex that allows co-amplification and fluorescent detection of 27 loci, including Amelogenin, 23 autosomal STR loci and 3 Y chromosome STR loci....

Numerous studies demonstrated that STRs have become powerful tools in forensic case work.To profile DNA samples from 104 Turkish males for 13 autosomal, STR markers intended for human identification purposes and to estimate the allele frequency distribution in forensic cases in a Turkish population.Thirteen autosomal STR loci, namely D3S1358, D2S1338, D16S539, D8S1179, D21S11, D18S51, TH01, D13S317, D7S820, CSF1PO, TPOX, D5S818 and FGA, were analysed in a sample of 104 healthy and unrelated Turkish individuals who have been living in the city of İzmir. All loci were amplified by using AmpFlSTR Identifier Kit. Genetic analysis was carried out on an ABI PRISM 310 Genetic Analyser.For each locus, 6-15 alleles were found with frequencies ranging from 0.005-0.514 and heterozygosities ranging from 0.686-0.868. The PIC value was highly significant (0.999).The 13 STR loci in the AmpFlSTR Identifier Kit are suitable for forensic identification and paternity tests due to high heterozygosity. The observed PD value is sufficiently high for human identification purposes. In conclusion, the 13 STR loci seem to be useful markers for personal identification and forensic case work in the Turkish population. The results also demonstrate the importance of region-specific studies.

In this study we report the development of a generic protocol for preimplantation genetic diagnosis (PGD) of severe α-thalassemia (α-thal) syndromes in α-thal carrier couples of Mediterranean origin. The in silico identification and design of primers for multiplex analysis of short tandem repeats (STRs), was followed by the optimization of polymerase chain reaction (PCR) conditions for multiplexed STR analysis within the α-globin gene cluster (16p3.3) and subsequent optimization and validation of a single-cell multiplex reaction including the selected STRs. Three simple dinucleotide repeats were selected based on their rate of heterozygosity, multiplex PCR efficiency and product size, and location within the α-globin gene cluster. The multiplex PCR was optimized in single lymphocytes with PCR efficiency ranging from 92.5 to 98% and an allele drop-out (ADO) rate of 0 to 9.0% for the three loci. The optimized method was applied in two clinical PGD cycles and genotypes were achieved in 17 out of 18 blastomeres (94%). Transfer of unaffected embryos led to a singleton pregnancy in one of the two couples. The triplex PCR validated for Greek and Cypriot populations is a robust generic method for α-thal PGD.

Multiplexes of polymorphic tetranucleotide Short Tandem Repeats (STRs) are regularly employed for forensic identification and kinship testing. If the DNA profiles of two samples match, there is a high probability that the samples have originated from the same individual. Match probabilities are calculated to evaluate the strength of DNA evidence. Relatives often share more alleles than unrelated individuals. High allele sharing among relatives can complicate source attribution of a DNA profile. In this paper, a case of high allele sharing of autosomal STR loci between two full siblings is reported and implications in source attribution are discussed.

The Centre of Forensic Sciences, in both its Toronto and Northern Regional Laboratories (Sault Ste. Marie, Ontario), has completed internal validation of the Promega PowerPlex®16 DNA typing system in accordance with the revised SWGDAM validation guidelines (January 2004). The Promega PowerPlex®16 DNA typing system amplifies the 13 CODIS loci along with Penta D, Penta E, and Amelogenin in a single reaction, affording the laboratory greater efficiencies, discrimination power, and throughput. Methodologies, techniques and platforms already in place for current multiplex systems were employed. Detection of amplified product was achieved using 5% Long Ranger® Singel Polyacrylamide gels on ABI 377 Automated Sequencers. Robust performance of the PowerPlex®16 system was obtained using 1ng of target DNA in a 15 pL reaction amplified for a total of 30 PCR cycles. With these conditions, 0.5 pL of amplified product yielded average combined allelic peak heights in excess of 1000 rfu per locus. Sensitivity stud...