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Data of eight Y-chromosomal STRs, the so called "minimal core set", were obtained from 152 unrelated males of the Primorye region of Russia. The allelic frequencies correspond to other European populations. The background is a settlement of males from the European part of Russia, Ukraine and other states which were included in the former western part of the Soviet Union. On the other hand the distribution of the most frequent haplotypes differs to the Ukraine and Russian population. The most frequent haplotype was obtained five times in the population corresponding to 3.3%. The haplotype data reported here have been included into the Y-STR database maintained at the Institute of Legal Medicine, Humboldt-University, Berlin.

Y-chromosomal DNA polymorphisms, especially Y-STRs are well established in forensic routine case work. The STRs are used for identification in paternity deficiency cases and stain analysis with complicate mixtures of male and female DNA. In contrast, Y-chromosomal SNPs are a new tool in forensic investigations. At present, Y-SNPs are mainly used in molecular anthropology for evolutionary studies. Nevertheless, these markers could also provide very useful information for the analysis of forensic cases. The aim of the presented study was to test Y-SNP-typing for stain analyses using different methods-SNaPshot and MALDI-TOF MS. Both methods are based on the principle of minisequencing. The selected Y-SNP markers are suited to define the most important European haplogroups.

Degradation of human DNA extracted from forensic stains is, in most cases, the result of a natural process due to the exposure of the stain samples to the environment. Experiences with degraded DNA from casework samples show that every sample may exhibit different properties in this respect, and that it is difficult to systematically assess the performance of routinely used typing systems for the analysis of degraded DNA samples. Using a batch of artificially degraded DNA with an average fragment size of approx. 200 bp a collaborative exercise was carried out among 38 forensic laboratories from 17 European countries. The results were assessed according to correct allele detection, peak height and balance as well as the occurrence of artefacts. A number of common problems were identified based on these results such as strong peak imbalance in heterozygous genotypes for the larger short tandem repeat (STR) fragments after increased PCR cycle numbers, artefact signals and allelic drop-out. Based on the observations, strategies are discussed to overcome these problems. The strategies include careful balancing of the amount of template DNA and the PCR cycle numbers, the reaction volume and the amount of Taq polymerase. Furthermore, a careful evaluation of the results of the fragment analysis and of automated allele calling is necessary to identify the correct alleles and avoid artefacts.

As fatal trauma to the neck is often associated with short survival times, proof of vitality may often be difficult using standard histochemical techniques. Soft tissue neck injuries resulting from strangulation by ligature or manual strangulation were examined immunohistochemically using antibodies to myoglobin, fibronectin, C5b-9 and MRP14, and compared to controls consisting of accidental soft tissue neck injuries as well as undamaged neck soft tissue. Although survival times in the study and control groups were unknown and certainly some individual variation may be expected in the time course of normal wound development, both the study and control groups demonstrated similar time courses in the immunohistochemical detection of antigen. Myoglobin was always found in those samples in which only one antigen was shown to be involved in an injury-specific pattern; myoglobin and fibronectin were found in samples with dual antigen involvement. Samples involving three antigens always included C5b-9 in addition to myoglobin and fibronectin. The single positive MRP14 sample in the study and control groups was simultaneously positive for the other markers used. Myoglobin, fibronectin, C5b-9 and MRP14 are therefore suitable for immunohistochemical detection of vital reactions and estimation of temporal relationships in the early posttraumatic period after neck trauma.

Allele frequencies for 16 X-linked STRs, suitable for forensic purposes, were obtained from a sample of unrelated German individuals (male and female). The presented data show also repeat sequence structures and statistic parameters describing there information content.

Data of nine Y-chromosomal STRs, the so called "extended core set", were obtained from 152 unrelated males from Lithuania, 145 from Latvia and 133 from Estonia. The haplotype data reported here have been included into the Y-STR database maintained at the Institute of Legal Medicine, Humboldt-University, Berlin.

Close co-operation between forensic scientists, medico-legal doctors, and police forces made it possible to estimate not only the post-mortem interval but also the time since a child was neglected. On the skin surface under the diaper (anal-genital area), third instar larvae of the false stable fly Muscina stabulans FALLEN, and the lesser house fly Fannia canicularis L. were found. F. canicularis adults are attracted to both feces and urine. From the face, larvae of the bluebottle fly Calliphora vomitoria L. were collected. C. vomitoria maggots are typical early inhabitants of corpses. From the developmental times of the flies, it was estimated that the anal-genital area of the child had not been cleaned for about 14 days (7-21 day range), and that death occurred only 6-8 days prior to discovery of the body. This is the first report where an examination of the maggot fauna on a person illustrated neglect that had occurred prior to death.

The reference database of highly informative Y-chromosomal short tandem repeat (STR) haplotypes (YHRD), available online at http://ystr.charite.de, represents the largest collection of male-specific genetic profiles currently available for European populations. By September 2000, YHRD contained 4688 9-locus (so-called "minimal") haplotypes, 40% of which have been extended further to include two additional loci. Establishment of YHRD has been facilitated by the joint efforts of 31 forensic and anthropological institutions. All contributing laboratories have agreed to standardize their Y-STR haplotyping protocols and to participate in a quality assurance exercise prior to the inclusion of any data. In view of its collaborative character, and in order to put YHRD to its intended use, viz. the support of forensic caseworkers in their routine decision-making process, the database has been made publicly available via the Internet in February 2000. Online searches for complete or partial Y-STR haplotypes from evidentiary or non-probative material can be performed on a non-commercial basis, and yield observed haplotype counts as well as extrapolated population frequency estimates. In addition, the YHRD website provides information about the quality control test, genotyping protocols, haplotype formats and informativity, population genetic analysis, literature references, and a list of contact addresses of the contributing laboratories.

Y-chromosomal microsatellites (STRs) are potentially useful in forensic practice but, in contrast to autosomal systems, large and diverse population databases are required in order to facilitate the statistical evaluation of donor-stain matches. Since appropriate data from the Baltic region have so far been lacking, blood samples were obtained from 430 males originating from one of the three Baltic states and these samples were genotyped using a previously described "extended core set" of nine Y-STR marker systems. Allele frequency distributions and discrimination indices were calculated, and the three populations were tested for genetic differences by means of analysis of molecular variance (AMOVA). A larger genetic difference became apparent between Estonian and both Lithuanian and Latvian males than between the latter two, non-Finno-Ugric speaking populations. The haplotype data reported here have been included into the Y-STR database maintained at the Institute of Legal Medicine, Humboldt University, Berlin.

A 9-locus microsatellite framework (minimal haplotype), previously developed for forensic purposes so as to facilitate stain analysis, personal identification and kinship testing, has been adopted for the establishment of a large reference database of male European Y-chromosomal haplotypes. The extent of population stratification pertaining to this database, an issue crucial for its practical forensic application, was assessed through analysis of molecular variance (AMOVA) of the 20 regional samples included. Despite the notion of some significant haplotype frequency differences, which were found to correlate with known demographic and historic features of Europeans, AMOVA generally revealed a high level of genetic homogeneity among the populations analyzed. Owing to their high diversity, however, accurate frequency estimation is difficult for Y-STR haplotypes when realistic (i.e. moderately sized) datasets are being used. As expected, strong pair-wise and higher order allelic associations were found to exist between all markers studied, implying that haplotype frequencies cannot be estimated as products of allele frequencies. A new extrapolation method was therefore developed which treats haplotype frequencies as random variables and generates estimates of the underlying distribution functions on the basis of closely related haplotypes. This approach, termed frequency 'surveying', is based upon standard population genetics theory and can in principle be applied to any combination of markers located on the Y-chromosome or in the mitochondrial genome. Application of the method to the quality assured reference Y-STR haplotype database described herein will prove very useful for the evaluation of positive trace-donor matches in forensic casework.

In order to apply a useful STR system we performed a population study in Western Saxony (Germany). The allele distribution was investigated in a sample of 431 unrelated adults. In addition, 170 families from routine paternity cases were examined for the presence of meiotic mutations, and two mutations were observed.