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A large number of 186 Y-STR markers in nearly 2000 DNA-confirmed father-son pairs, covering an overall number of 352,999 meiotic transfers were analyzed to determine the key requirement for application of Y-chromosomal microsatellites (Y-STRs) which are widely used to infer population histories. The findings from the study might provide important insight into Y-chromosomal applications in forensic biology and identify future male individual from previous male lineage differentiation.

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2007.10.005 Byline: Christina Kaiser (a), Beatrice Bachmeier (b), Claudius Conrad (c), Andreas Nerlich (d), Hansjurgen Bratzke (a), Wolfgang Eisenmenger (e), Oliver Peschel (e) Keywords: Bone; Forensic; DNA degradation; Time since death; Postmortem interval (PMI) Abstract: In the past years, many publications about identification and sex-determination of dry human bones by means of DNA analysis have been published. However, few studies exist that investigate the potential use of DNA technique to determine the postmortem interval (PMI). In the present study we analyzed the rate of increasingly smaller fragments of chromosomal DNA and PMI. We examined DNA degradation in human bones with postmortem intervals ranging between 1 and more than 200 years that had been kept under comparable conditions concerning weather and soil. Following bone separation into the three different zones of interest of inner/middle/outer segments the quantity of total DNA was determined in each region. Subsequently, the degree of DNA fragmentation was estimated by searching for PCR products of defined size (150, 507 and 763bp) with primers of the human-specific multicopy [beta]-actin-gene. Concerning DNA quantity we detected a significant correlation between the zone of interest and the amount of DNA. However, there was no correlation between the amount of DNA and PMI. In contrast to this, analyzing DNA using PCR showed a significant inverse correlation between fragment length and PMI. Thus, postmortem DNA degradation into increasingly smaller fragments reveals a time-dependent process. It has the potential to be used as a predictor of PMI in human bone findings, provided that environmental conditions are known. Author Affiliation: (a) Centre of Legal Medicine, University of Frankfurt/Main, Kennedyallee 104, 60596 Frankfurt/Main, Germany (b) Department of Clinical Chemistry and Clinical Biochemistry, University of Munich, Munich, Germany (c) Department of Surgery, Massachusetts General Hospital, Boston, MA, USA (d) Institute of Pathology, Academic Hospital Munich-Bogenhausen, Munich, Germany (e) Department of Legal Medicine, University of Munich, Munich, Germany Article History: Received 22 May 2007; Accepted 10 October 2007

To link to full-text access for this article, visit this link: http://dx.doi.org/10.1016/j.forsciint.2006.05.042 Byline: S. Amory (a)(b), C. Keyser (a)(b), E. Crubezy (b), B. Ludes (a) Keywords: Ancient DNA; STR; Y chromosome; Hair shaft; Siberia Abstract: The aim of this study was to determine if ancient hair shafts could be suitable for nuclear DNA analysis and to develop an efficient and straightforward protocol for DNA extraction and STR typing of ancient specimens. The developed method was validated on modern and forensic samples and then successfully applied on ancient hairs collected from Siberian mummies dating from the 16th to the early 19th centuries. In parallel extractions including or excluding a washing step were performed at least two times for each sample in order to evaluate the influence on the quantity of nuclear DNA yielded and on the typing efficiency. Twelve ancient individuals were analyzed through our approach and full and reliable profiles were obtained for four of them. These profiles were validated by comparison with those obtained from bone and teeth DNA extracted from the same ancient specimens. The present study demonstrates that the washing step cannot be considered as deleterious for DNA retrieval since the same results were obtained by the two approaches. This finding challenges the hypothesis that recoverable nuclear DNA is only found on the outer surface of hair shafts and provides evidence that nuclear DNA can be successfully extracted from ancient hair shafts. The method described here constitutes a promising way for non-invasive investigations in ancient DNA analysis for precious or historical samples as well as forensic casework analyses. Author Affiliation: (a) Laboratory of Molecular Anthropology, Institute of Legal Medicine of Strasbourg, 11 rue Humann, 67085 Strasbourg Cedex, France (b) Laboratory of Anthropo-biology, UMR 8555, CNRS, 39 allees Jules Guesde, 31400 Toulouse, France Article History: Received 5 May 2006; Revised 22 May 2006; Accepted 24 May 2006

Seven Y-chromosome microsatellite loci (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) were analyzed in three populations from sub-Saharan Africa: the Bamileke and Ewondo populations from Cameroon and the Hutu from Rwanda. Complete typing was obtained for 112 individuals, and a total of 53 different haplotypes was observed. The single-locus gene diversity, averaged across populations, ranges from 0.100 for the DYS392 locus to 0.610 for the DYS389I locus. The haplotype diversity ranges from 0.832 (Ewondo) to 0.965 (Hutu), with an intermediate value of 0.918 in the Bamileke. The diversity among Bamileke, Ewondo, Hum, and other sub-Saharan populations selected from the literature was analyzed using both a classical ([F.sub.ST]) and a stepwise-based ([R.sub.ST]) genetic distance method. The pattern of interpopulational diversity based on [F.sub.ST] was congruent with anthropological knowledge, while that based on [R.sub.ST] revealed unexpected and unconvincing population affinities. From a practical point of view, our study indicates that Y-chromosome microsatellite data may provide useful information for analyses of interpopulational diversity among sub-Saharan populations if an adequate number of loci and individuals along with an appropriate genetic distance method are used. On a theoretical ground, we propose that the lesser performance of [R.sub.ST] compared to [F.sub.ST] could be explained by the important role played by genetic drift in shaping the relationships among examined populations. KEY WORDS: Y CHROMOSOME. MICROSATELLITE. HAPLOTYPES, BAMILEKE, EWONDO, HUTU, In the last few years a large amount of data concerning Y-chromosome haplotypes based on microsatellites located on the nonrecombining region has been published (Deka et al. 1996; de Knjiff [...]

Genetic diversity at the nine short tandem repeat (STR) loci, which are universally approved and widely used for forensic investigations, has been studied among nine Indian populations with diverse ethnic, linguistic, and geographic backgrounds. The nine STR loci were profiled on 902 individuals using fluorescent detection methods on an ABI377 System, with the aid of an Amp-Fl Profiler Plus Kit. The studied populations include two upper castes, Brahmin and Kayastha; a tribe, Garo, from West Bengal; a Hindu caste, Meitei, with historical links to Bengal Brahmins; a migrant group of Muslims; three tribal groups, Naga, Kuki and Hmar, from Manipur in northeast India; and a middle-ranking caste, Golla, who are seminomadic herders from Andhra Pradesh. Gene diversity analysis suggests that the average heterozygosity is uniformly high (>0.8) in the studied populations, with the coefficient of gene differentiation at 0.050 ± 0.0054. Both neighbor-joining (NJ) and unweighted pair group method with arithmetic mea n (UPGMA) trees based on [D.sub.A] distances bring out distinct clusters that are consistent with ethnic, linguistic, and/or geographic backgrounds of the populations. The fit of the Harpending and Ward model of regression of average heterozygosity on the gene frequency centroid is found to be good, and the observed outliers are consistent with the population structure and history of the studied populations. Our study suggests that the nine STR loci, used so far mostly for forensic investigations, can be used fruitfully for microevolutionary studies as well, and for reconstructing the phylogenetic history of human populations, at least at the local level., ********** RANJAN DUTTA (1,3) B. MOHAN REDDY (2) P. CHATTOPADHYAY (3) V.K. KASHYAP (3) GUANGYUN SUN (4) RANJAN DEKA (4) The Indian subcontinent is considered a natural laboratory for population [...]

The recent article criticizing current methods in forensic DNA typing by R. C. Lewontin and Daniel E. Hartl (20 Dec., p. 1745) is very properly criticized in turn by Ranajit [...]

AFTER THE DISCOVERY IN 1980 OF A HYPERVARIABLE DNA polymorphism in the human genome [1] and the subsequent demonstration that such hypervariability is widespread in humans [2], forensic scientists have [...]

Variable number of tandem repeat (VNTR) sequences are used to link defendants with crimes by matching DNA patterns. The probative value of a match is often calculated by multiplying together the estimated frequencies with which each particular VNTR pattern occurs in a reference database. However, this method is liable to potentially serious errors because ethnic subgroups within major racial categories exhibit genetic differences that are maintained by endogamy. The multiplication procedure currently in use can be made scientifically valid only by extensive sampling of VNTR frequency distributions in a variety of ethnic groups, similar to the ethnic studies of various blood groups done in the past. Alternative approaches for dealing with subpopulation heterogeneity are discussed., FORENSIC SCIENTISTS ARE CONSTANTLY SEARCHING FOR Biological characteristics that are so variable among individuals that an observed match found in material left at the scene of the crime could be [...]

A study was conducted to analyze the use of canine microsatellite polymorphisms in forensic examination. Polymerase chain reaction was carried out for three different loci. The PCR products were then denatured by adding three volumes of SSCP loading buffer at 94 degrees C. Experimental results indicated the possibility of excluding candidates by the SSCP-analysis of polymorphic canine microsatellites.

The US National Academy of Sciences launched a study of the use of DNA evidence in court cases, as requested by the Federal Bureau of Investigation. Accurate calculations and careful presentation of statistical probabilities of discrepancies in DNA reports facilitate unbiased adjudication. This study will proceed if the National Research Council raises the necessary finance for this venture.

Out of the Mouths of Terrorists Genetic fingerprinting, a technique that produces a visual representation of a person's genome, has since its discovery in 1985 been used by criminal investigators [...]