Forensic identification of urine samples: a comparison between nuclear and mitochondrial DNA markers

Urine samples from 20 male volunteers of European Caucasian origin were stored at 4°C over a 4-month period in order to compare the identification potential of nuclear DNA (nDNA) and mitochondrial DNA (mtDNA) markers. The amount of nDNA recovered from urines dramatically declined over time. Consequently, nDNA likelihood ratios (LRs) greater than 1,000 were obtained for 100, 70 and 55% of the urines analysed after 6, 60 and 120 days, respectively. For the mtDNA, HVI and HVII sequences were obtained for all samples tested, whatever the period considered. Nevertheless, the highest mtDNA LR of 435 was relatively low compared to its nDNA equivalent. Indeed, LRs obtained with only three nDNA loci could easily exceed this value and are quite easier to obtain. Overall, the joint use of nDNA and mtDNA markers enabled the 20 urine samples to be identified, even after the 4-month perio

The Western and Eastern Roots of the Saami - The Story of Genetic "Outliers" Told by Mitochondrial DNA and Y Chromosomes

Funding Information: We thank Tatyana Karafet and Boris Malyarchuk, for useful information; Henry Harpending, for the program POPSTR; Vincent Macaulay, for the program SAMPLING; Ille Hilpus and Jaan Lind, for technical assistance; and Charles Kurland and Thomas Gilbert, for helpful discussion and comments. We are grateful to two anonymous reviewers for their suggestions and advice. The research of R.V. was supported by Estonian basic research grant 514 and European Commission Directorate General Research grant ICA1CT20070006. The research of T.K. was supported by Estonian basic research grant 5574. The work of E.K. was supported by the Russian Foundation for Basic Research (project number 01-04-48487a) and the Ministry of Sciences and Technology of Russia. M.G., S.Z., and L.O. received support from expedition grants from the Siberian Branch of the Russian Academy of Sciences (1992–1997) and the Russian Foundation of Basic Research (project number 02-06-80524-a), and the research of P.R. received support from project number 0196005 of the Ministry of Science and Technology of the Republic of Croatia.The Saami are regarded as extreme genetic outliers among European populations. In this study, a high-resolution phylogenetic analysis of Saami genetic heritage was undertaken in a comprehensive context, through use of maternally inherited mitochondrial DNA (mtDNA) and paternally inherited Y-chromosomal variation. DNA variants present in the Saami were compared with those found in Europe and Siberia, through use of both new and previously published data from 445 Saami and 17,096 western Eurasian and Siberian mtDNA samples, as well as 127 Saami and 2,840 western Eurasian and Siberian Y-chromosome samples. It was shown that the "Saami motif" variant of mtDNA haplogroup U5b is present in a large area outside Scandinavia. A detailed phylogeographic analysis of one of the predominant Saami mtDNA haplogroups, U5b1b, which also includes the lineages of the "Saami motif," was undertaken in 31 populations. The results indicate that the origin of U5b1b, as for the other predominant Saami haplogroup, V, is most likely in western, rather than eastern, Europe. Furthermore, an additional haplogroup (H1) spread among the Saami was virtually absent in 781 Samoyed and Ob-Ugric Siberians but was present in western and central European populations. The Y-chromosomal variety in the Saami is also consistent with their European ancestry. It suggests that the large genetic separation of the Saami from other Europeans is best explained by assuming that the Saami are descendants of a narrow, distinctive subset of Europeans. In particular, no evidence of a significant directional gene flow from extant aboriginal Siberian populations into the haploid gene pools of the Saami was found.Peer reviewe

Evaluation and usefulness of reverse dot blot DNA-PolyMarker typing in forensic case work.

Experiments were performed to evaluate the Amplitype PolyMarker DNA typing system for application to forensic casework. DNA extraction using chelex was compared with phenol-chloroform extraction for various biological materials including postmortem blood, blood samples used for alcohol quantification, fresh urine, envelopes and cigarette butts. Different amounts of genomic DNA were amplified to test the sensitivity of the Amplitype PM. Mixed samples of two different bloods were typed to determine the dilution at which mixtures could be detected. Different storage conditions were evaluated using urine samples. Postmortem blood samples were typed during 4 months to determine the effects of natural degradation. A population sample of 105 unrelated individuals from South-West Switzerland was analyzed and the genotype frequencies were compared with those reported by others. Finally, practical usefulness of the Amplitype PM system is illustrated by analysing casework samples. The results of this validation proved the great usefulness and sensitivity of the Amplitype PM system using the appropriate extraction and typing method. However, mixed samples had to be interpreted with caution owing to the possibility of non-specific alleles with stored material such as urine and postmortem blood

Chemiluminescent DNA probes: evaluation and usefulness in forensic cases.

Five phosphatase-labelled oligonucleotide probes were evaluated in respect to their sensitivity, with the help of an optimized chemiluminescent protocol, for DNA-VNTR polymorphism determination. Their usefulness for the identification of biological traces is illustrated with casework examples

A plasminogen silent allele detected in a Swiss family.

An apparent incompatibility between mother and child in the plasminogen system has been clarified by the demonstration of a silent allele in the family

F13B and CD4 allele frequencies in south west Switzerland.

Allele frequencies of the two short tandem repeat (STR) systems F13B and CD4 were determined in a population sample from South West Switzerland using PCR analysis. We found five alleles for both STRs in a population sample of 205 unrelated individuals. No significant deviation from Hardy-Weinberg equilibrium was observed