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Our laboratory has developed an automated real-time quantitative PCR assay for detecting human DNA. The assay utilizes an inhouse, custom-designed TaqMan®-MGB sequence-specific probe (CFS-rHumRT) and the ABD 7900HT SDS platform. Developmental validation has followed TWGDAM (1) guidelines and demonstrates that the assay is primate specific, is highly sensitive, yields consistent results, and works with human DNA extracted from a variety of body fluid stains. When operating within the dynamic range of the system using high-quality DNA samples, the technique yields similar quantification results to our current QuantiBlot™ assay with the added benefit of time saving through automation. Furthermore, the QPCR assay identifies how much amplifiable DNA is in a sample and thus has the potential to predict PCR success in downstream applications such as STR analysis.

An interlaboratory comparison of typing results for Short Tandem Repeats (STRs) at the GenBank loci HUMCSF1PO, HUMTPOX, HUMTH01, and HUMVWFA31 using the “CTT triplex” and “CTTv quadruplex” has been evaluated. These STRs all have a nominal four basepair (bp) repeat. Seven different samples were distributed to 41 laboratories. The 34 laboratories that returned results used a wide variety of analytical systems. Comparable results were obtained for all samples at all loci when results were reported as an allelic name. Raw sizing results obtained from internal-lane sizing standards differed by nearly five bp at some loci. Many different factors contribute to this observed sizing variability, including choice of sizing standards and matrix composition. Although sizing results can be made more comparable by locus-specific offsets or calibration to a comprehensive set of alleles at each locus, samples typed to the allelic name can now be validly compared regardless of analytical method. Interlaboratory comparison of raw allelic size remains problematic.

We tested the cross-amplification of 37 microsatellites in a population of starlings ( Sturnus vulgaris ). Twenty-three of them amplified and five exhibited a large number of alleles per locus and high heterozygosity (on average: 14.6 alleles / locus and H E = 0.704). We assessed the occurrence of extra-pair paternity (EPP) and intraspecific brood parasitism (IBP) in this population. The EPP rate was 16 % to 18% offspring from 43% to 45% of nests. IBP was very variable between two successive years (14% to 27% chicks from 25% to 64% of clutches). These five polymorphic markers will be of potential use in studies of genetic diversity, population structure and reproductive strategy of this species.