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At least 577 records · Page 32Linked to original sources
PubMed1994

Variation in short tandem repeat sequences--a survey of twelve microsatellite loci for use as forensic identification markers.

Alleles at 12 Short Tandem Repeat loci have been sequenced to investigate candidate loci for a multiplex Short Tandem Repeat system for forensic identification, and for single-locus amplification of Short Tandem Repeat loci. Variation from the consensus sequence was found at 6 loci, while one locus, D21S11, was found to be complex in sequence. The presence of non-consensus alleles does not rule out loci for inclusion as forensic identification markers, but size differences between alleles of 1 base pair require very precise sizing. We suggest criteria for the suitability of Short Tandem Repeat loci as forensic identification markers, and propose a universal allele nomenclature for simple and compound Short Tandem Repeats. The effect of the repeat unit sequence of the evolution of Short Tandem Repeats is discussed.

Alleles↗
PubMed1979

[The detection of gamma globulin and Inv-factors in semen and saliva and of haptoglobins in semen (author's transl)].

Gm- 1-, 2-, and Inv 1-factors can be demonstrated in semen and saliva. For the examination of traces it is necessary to verify the suitable dilutions for the different charges of antisera and to test the eluates of the samples if they have a sufficient concentration. We observed some incorrect negative results in seminal and saliva stains which were apparently caused by insufficient material. The demonstration was independent of the secretor type. Haptoglobin could not be determined in semen and saliva.

Forensic Medicine↗
PubMed2000

Forensic evaluation of mtDNA in a population from south west Switzerland.

The polymorphism of the two hypervariable segments (HVI and HVII) of the control region of mtDNA was analyzed in a population of 154 unrelated individuals from south west Switzerland using a fluorescent based capillary electrophoresis sequencing method. In our population data of 154 random individuals, 137 mtDNA types were observed. Of these, 124 sequences were observed only in one individual whereas 10 sequences were observed in 2 individuals, 2 sequences in 3 individuals and 1 sequence in 4 individuals. The probability of two unrelated individuals having the same sequence was 0.84%. The results were compared with four other Caucasian populations. Furthermore, the usefulness of the mtDNA sequencing was tested, for exclusion and inclusion, in 18 forensic cases including 69 evidence samples and 44 reference samples. Despite the fact that 55% of the evidence samples yielded a negative result for the nuclear DNA with the human dot quantitation system, the success rate of the mtDNA sequencing was 71.0%. This validation study proves the great usefulness and sensitivity of the mtDNA sequencing technique using nested PCR and fluorescent capillary electrophoresis.

DNA, Mitochondrial↗
PubMed2002

Continental and subcontinental distributions of mtDNA control region types.

When the mtDNA profile of a crime scene matches that of a suspect, it is necessary to determine the probability of a chance match by consulting the frequencies of the identified allele in a "reference population". The ceiling principle suggests that that population should be chosen in which the allele of the suspect is found at the highest frequency, in order to give the suspect the maximum benefit of doubt. Recently, we advocated the use of a worldwide mitochondrial database combined with a geographical information system to identify the regions of the world with the highest frequencies of matching mtDNA types. Here, we demonstrate that the alternative approach of defining a ceiling reference population on the basis of continent or phenotype (race) is too coarse for a non-negligible percentage of mtDNA control region types.

DNA, Mitochondrial↗
PubMed2002

JC virus genotyping offers a new means of tracing the origins of unidentified cadavers.

There has been no reliable means of tracing the origins of unidentified cadavers but the recent finding that JC virus (JCV) can serve as a means of elucidating human migrations suggested that this virus may also be useful to trace the origins of unidentified cadavers. DNA samples extracted from renal tissue and urine were used as the template for PCR amplification of a 610 bp region (IG region) of the viral genome. We detected JCV DNA in 45% of the renal samples and in 33% of the urine samples and was detectable even 10 days after death. The sequences of the amplified IG regions could be used to determine the genotypes. We conclude that the JC virus genotype is a new marker useful for tracing the origins of unidentified cadavers.

Cadaver↗
PubMed2002

Polymorphism of nine X chromosomal STR loci in Koreans.

This study describes the polymorphism of the nine STR loci on the X chromosome, DXS6803, DXS8378, GATA164A09, DXS7132, DXS7133, DXS9895, DXS9898, DXS6789, and DXS6795 in Koreans. In each locus, 4-10 alleles were noted and the allelic distribution patterns were the same for males and females. Heterozygosity in females ranged from 0.42 to 0.84. Among the 303 father-daughter or mother-child pairs examined 29 cases of mutation were found, 13 at the DXS6803 locus, 2 at DXS8378, 4 at DXS164A09, 3 at DXS7132, 1 at DXS7133, 2 at DXS9895, 2 at DXS9898, 1 at DXS6789 and 1 at DXS6795. In 208 families including 180 fathers and 177 mothers, 530 different haplotypes were found. Unlike the STR loci on the Y chromosome, cases showing recombination were frequent, and in combination with mutation this made it difficult to discriminate the exclusion cases from those with mutation or recombination based on the haplotype. Details of X chromosomal STRs in Koreans which would be useful for a future large scale database are described.

Adult↗
PubMed2003

Characterization of eight Y-STR loci and haplotypes in a Chinese Han population.

In this study we analyzed the eight Y-STR loci, DYS443, DYS444, DYS448, DYS453, DYS455, DYS456, DYS457 (DYS437) and DYS458, investigated haplotype distributions of these Y-STR loci in a Chinese Han population, and sequenced alleles of the eight loci for clarifying the structure. Extracted DNA was amplified by PCR and the PCR products were analyzed by non-denaturing horizontal polyacrylamide gel electrophoresis with a discontinuous buffer system. Alleles were sequenced on an ABI 3700 using a Dye Terminator Cycle sequencing kit. DYS443, DYS453, DYS455 and DYS456 were found to be simple repeat systems, while DYS444, DYS448, DYS457 (DYS437) and DYS458 were complex repeat systems. The gene diversities of DYS443, DYS444, DYS448, DYS453, DYS455, DYS456, DYS457 (DYS437) and DYS458 were 0.7742, 0.7671, 0.7453, 0.3545, 0.0549, 0.6988, 0.6148 and 0.8213, respectively. The haplotype diversity for 8 Y-STR loci was 0.9996, and the discrimination capacity was 0.9815. The results indicate that these eight loci are useful Y-linked markers for forensic applications.

Alleles↗
PubMed2003

Y-chromosomal STR haplotypes in a population sample from southwest Germany (Freiburg area).

In the present study Y-chromosomal short tandem repeat (Y-STR) haplotypes of 433 unrelated male individuals from southwest Germany (Freiburg area) were analyzed. Population data for the loci DYS19, 389I, 389II, 390, 391, 392, 393, 385 and YCA II are given. Analysis of these loci provides the data that is defined as the "extended haplotype" and is available in the on-line Y-STR haplotpye reference database (YHRD) at http://ystr.org. Special emphasis is placed on the sequence and nomenclature of YCA II.

Base Sequence↗
PubMed2003

Evaluating forensic DNA mixtures with contributors of different structured ethnic origins: a computer software.

The effect of a structured population on the likelihood ratio of a DNA mixture has been studied by the current authors and others. In practice, contributors of a DNA mixture may belong to different ethnic/racial origins, a situation especially common in multi-racial countries such as the USA and Singapore. We have developed a computer software which is available on the web for evaluating DNA mixtures in multi-structured populations. The software can deal with various DNA mixture problems that cannot be handled by the methods given in a recent article of Fung and Hu.

Alleles↗
PubMed2003

Sequence polymorphisms of the mitochondrial DNA control region and phylogenetic analysis of mtDNA lineages in the Japanese population.

Sequence polymorphisms of the hypervariable mitochondrial DNA (mtDNA) regions HVI and HVII, and coding region polymorphisms were investigated in 211 unrelated individuals from the Japanese population. Sequence comparison of the HVI and HVII regions led to the identification of 169 mitochondrial haplotypes defined by 147 variable positions. Among them 145 types were observed in only 1 individual; the other 24 types were shared by 2 or more individuals. The gene diversity was estimated at 0.9961, and the probability of two randomly selected individuals from the population having identical mtDNA types was 0.86%. We also established phylogenetic haplogroups in the Japanese population based on the coding and control region polymorphisms and compared the haplotypes with those in other Japanese, Korean and Chinese populations. As a result, three new subhaplogroups, G4a, G4b, and N9b, and several haplotypes specific for the Japanese and Korean populations were identified. The present database can be used not only for personal identification but also as an aid for geographic or phenotype (race) estimation in forensic casework in Japan.

Base Sequence↗
PubMed2003

Estimating the number of contributors to a DNA profile.

The broad topic of this paper is the evaluation of DNA evidence in criminal cases. More specifically, we deal with mixture evidence which refers to cases where there are, or could be, several contributors to a biological stain based on, e.g., blood or semen. The present paper addresses DNA mixtures based on single nucleotide polymorphism (SNP) markers, i.e., diallelic markers. Based on STR analysis, it is in most cases easy to identify the presence of a mixture since three or four bands will show up with a high probability for at least one locus. Obviously, this will not be the case for diallelic markers and interpreting mixtures will be a great challenge. We address this problem by first approaching the more general problem of estimating the number of contributors to a stain. In addition we discuss how the markers should be selected and how many are required.

Body Fluids↗
PubMed2004

Artificial recombination in forensic mtDNA population databases.

Artificial recombination of two or more mitochondrial DNA fragments from different samples would constitute a serious cause of error in forensic DNA typing, and yet one can demonstrate that such events have happened in the preparation of several published mtDNA databases. Focussed database searches, phylogenetic analysis, and network representations can highlight mosaic patterns and thus pinpoint sample mix-up. Therefore, we suggest that this approach should be applied to data prior to publication in order to uncover such errors in time.

DNA Fingerprinting↗
PubMed2004

Development of the AmpFISTR SEfiler PCR amplification kit: a new multiplex containing the highly discriminating ACTBP2 (SE33) locus.

The AmpFISTR SEfiler kit co-amplifies 11 short tandem repeat loci including SE33 in a single multiplex. After establishing the optimum in primer titration studies, the primer concentrations of all loci in the multiplex were chosen such that the heterozygote peak height ratios of each of the loci were balanced. The combined primer set was then tested to determine the robustness of the multiplex under various conditions. Different MgCl(2) concentrations were evaluated to establish the optimum concentration for the multiplex. The amplification of the various loci in the multiplex was tested at several annealing temperatures (55-63 degrees C). Additionally, DNA from primates, non-primates and microorganisms were amplified to investigate the specificity of the kit. The stability of the AmpFISTR SEfiler kit was determined by addition of hematin, to simulate inhibition, and the use of degraded DNA. Population studies revealed a probability of identity of 6.47x10(-15) for African Americans and 7.46x10(-14) for US Caucasians. To assess the ability of the multiplex to analyze forensic samples, testing on blood, oral swabs and mixtures was performed. Based on the various studies, it was determined that the AmpFISTR SEfiler PCR amplification kit can be used to successfully analyze a variety of forensic, databasing and paternity samples.

Animals↗