Search results for "pathology [Brain Neoplasms]"
showing 10 items of 1714 documents
Considerations from the European DNA profiling group (EDNAP) concerning STR nomenclature
1997
(1) The nomenclature of any STR follows from comparison with a control allelic ladder; availability of reference allelic ladders is central to any scheme. The components of an allelic ladder should be sequenced. (2) The DNA commission recommended a nomenclature based upon the number of repeat sequences present in an allele. Whereas this method is suitable for typing simple STRs, complex hypervariable repeats such as ACTBP2 do not conform to a simple repeating structure. We propose that designation of complex STR repeats such as ACTBP2, D11S554 and APOAI1 follows from the size of specific alleles. Because the size is dependant upon the primers utilised, the size is not definitive (it may als…
Results of collaborative study regarding the standardization of the Y-linked STR system DYS385 by the European DNA Profiling (EDNAP) group.
1999
Y-chromosome linked short tandem repeat (STR) loci are inherited as a closely linked haplotype, which appears to remain stable in a given paternal lineage over many generations. In forensic cases, Y-linked STRs are particularly useful for the identification of human remains as well as in rape cases with mixed male/female stain samples. DYS385 is derived from tandemly duplicated segments of the Y chromosome thus giving rise to two fragments of variable length which do not behave like alleles but genotypes. The European DNA Profiling (EDNAP) group has carried out a collaborative exercise among 14 participating laboratories using DYS385 for typing of five unknown bloodstains and a control samp…
Biostatistical basis of individualization and segregation analysis using the multilocus DNA probe MZ 1.3: results of a collaborative study.
1992
A collaborative study using the multilocus minisatellite DNA probe MZ 1.3 was carried out to investigate segregation information, mutation rate, DNA fragment frequencies as well as band sharing characteristics. The fingerprint patterns of 393 children as well as 694 unrelated individuals were analysed after digestion of DNA with the restriction enzyme HinfI. A mutation rate of 1% per meiosis or 0.04% per band was found with a mean number of 26 bands/individual. It was shown that maternal and paternal fragments are inherited in equal proportions. Population frequencies of restriction fragments demonstrated a distribution with increasing frequencies in the small fragment size range below 10 k…
Forensic mtDNA hair analysis excludes a dog from having caused a traffic accident
1999
A dog was suspected of having caused a traffic accident. Three hair fragments were recovered from the damaged car and subjected to DNA sequence analysis of the canine mitochondrial D-loop control region. The results were compared to saliva and hair samples from the alleged dog, as well as to control hair samples from four unrelated dogs of different breeds. Two sequence types exhibiting five nucleotide differences in a 377 bp fragment were identified among the four controls. Whereas the evidence hair fragment was identical to the type 1 control sequence, the alleged dog shared the type 2 control sequence except for one position. Thus the dog could be excluded as the origin of the hair fragm…
Results of a collaborative study of the EDNAP group regarding mitochondrial DNA heteroplasmy and segregation in hair shafts.
2004
Abstract A collaborative exercise was carried out by the European DNA Profiling Group (EDNAP) in order to evaluate the distribution of mitochondrial DNA (mtDNA) heteroplasmy amongst the hairs of an individual who displays point heteroplasmy in blood and buccal cells. A second aim of the exercise was to study reproducibility of mtDNA sequencing of hairs between laboratories using differing chemistries, further to the first mtDNA reproducibility study carried out by the EDNAP group [Forensic Sci. Int. 97 (1998) 165]. Laboratories were asked to type 2 sections from each of 10 hairs, such that each hair was typed by at least two laboratories. Ten laboratories participated in the study, and a to…
Basic issues in forensic DNA typing
1997
DNA analysis has become the standard method in forensic stain typing (termed DNA profiling). In contrast to conventional serological methods, any human tissue or body fluid can be analysed by DNA profiling as long as it contains nucleated cells. The majority of genetic systems studied at the DNA level are derived from "non-coding" portions from the human genome, and are located either in the vicinity of expressed (coding) genes or in stretches of DNA sequences interspersing with the genes. The typing results are usually recorded as DNA fragment lengths or "alleles" indicating the number of core repeat elements for short tandem repeat systems. These typing results do not contain any useful i…
A report of an international collaborative experiment to demonstrate the uniformity obtainable using DNA profiling techniques
1992
This paper describes a collaborative exercise intended to demonstrate whether uniformity of DNA profile results could be achieved between different European laboratories. It was shown that this goal can be obtained provided that a common protocol is followed (specifically the use of a common electrophoretic buffer as being the most important parameter). Generally, lower molecular weight loci (with lower molecular weight fragments) such as YNH24 perform better than higher molecular weight loci such as MS43a. The results of the exercise are discussed in relation to the objectives of the European DNA profiling group (EDNAP).
Extreme Methylation Values of Imprinted Genes in Human Abortions and Stillbirths
2010
Imprinted genes play an important role in fetal and placental development. Using quantitative bisulfite pyrosequencing assays, we determined the DNA methylation levels at two paternally methylated (H19 and MEG3) and four maternally methylated (LIT1, NESP55, PEG3, and SNRPN) imprinted regions in fetal muscle samples from abortions and stillbirths. Two of 55 (4%) spontaneous abortions and 10 of 57 (18%) stillbirths displayed hypermethylation in multiple genes. Interestingly, none of 34 induced abortions had extreme methylation values in multiple genes. All but two abortions/stillbirths with multiple methylation abnormalities were male, indicating that the male embryo may be more susceptible t…
Characterization of mutations and sequence variations in complex STR loci by second generation sequencing
2013
Abstract We used second generation sequencing (SGS) to examine sequence variation and mutational patterns in complex STR loci in Danish paternity cases. Four STR loci, D2S1338, D3S1358, D12S391 and D21S11, were sequenced in 45 samples from 15 confirmed trios with genetic inconsistencies between one of the parents and the child in either the D2S1338 or the D3S1358 loci. In 12 of the 15 cases, SGS revealed the allele that had mutated from the parent. In total, 61 different alleles were found in the 30 unrelated individuals. The highest variation was observed in the D12S391 locus and the lowest one in the D3S1358 locus. The four STR loci are good candidate loci for future SGS kits for forensic…
Recovery of Fusarium oxysporum Fo47 mutants affected in their biocontrol activity after transposition of the Fot1 element
2002
Trouvelot, S., Olivain, C., Recorbet, G., Migheli, Q., and Alabouvette, C. 2002. Recovery of Fusarium oxysporum Fo47 mutants affected in their biocontrol activity after transposition of the Fot1 element. Phytopathology 92:936-945. To investigate the biocontrol mechanisms by which the antagonistic Fusarium oxysporum strain Fo47 is active against Fusarium wilt, a Fot1 transposon-mediated insertional mutagenesis approach was adopted to generate mutants affected in their antagonistic activity. Ninety strains in which an active Fot1 copy had transposed were identified with a phenotypic assay for excision and tested for their biocontrol activity against F. oxysporum f. sp. lini on flax in greenho…