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Chin-Yuan Tzen Tsu-Yen Wu Hsin-Fu Liu 《Forensic Science International Supplement Series》2001,120(3):291
Analysis of the polymorphic sequences in mitochondrial DNA (mtDNA) has been widely applied to forensic tests and anthropology studies. However, these polymorphic data in human have thus far been derived from the displacement-loop and intergenic regions only. Here, we report the identification of clustered polymorphic sites in the mitochondria coding region encompassing position 8389–8865. The DNA sequences of 119 unrelated Chinese were determined by PCR amplification and direct sequencing. The results showed that heteroplasmy was found in five individuals, 39 sites were noted in this 477 bp region, and 41 haplotypes were identified. The probability of identity and allelic diversity were estimated as 0.1265 and 0.8809, respectively. The results suggest that sequence polymorphism from position 8389–8865 in human mtDNA can be used as a marker for identity investigation. 相似文献
884.
Robert E. Wenk M.D. M.S. Michael Baird Ph.D. John Peterson Ph.D. Debra Davis Ph.D. Richard Lieberman M.D. Janice M. Maly B.S. Lindsey J. Campbell B.S. Kathy K. Fox B.S. Kristin A. Schelling M.S. 《Journal of forensic sciences》2020,65(4):1346-1349
We were presented with the STR (short tandem repeat) profiles from two separate paternity trios. Each trio consisted of a mother, an alleged father, and products of conception (POC) that contained a hydatidiform mole but no visible fetus. In both cases , antecedent pregnancies had followed alleged sexual assaults. Mole classification and pathogenesis are described in order to explain the analyses and statistical reasoning used in each case. One mole exhibited several loci with two different paternal alleles, indicating it was a dispermic (heterozygous) mole. Maternal decidua contaminated the POC, preventing the identification of paternal obligate alleles (POAs) at some loci. The other mole exhibited only one paternal allele/locus at all loci and no maternal alleles, indicating it was a diandric and diploid (homozygous) mole. In each case, traditional calculations were used to determine paternity indices (PIs) at loci that exhibited one paternal allele/locus. PIs at mole loci with two different paternal alleles/locus were calculated from formulas first used for child chimeras that are always dispermic. Combined paternity indices in both mole cases strongly supported the paternity of each suspect. 相似文献
885.
Sydney I. Menchhoff M.S. Milady T. Delacruz Madison E. Hytinen B.S. Jordan O. Cox M.S. Marilyn T. Miller Ed.D. Tracey Dawson Cruz Ph.D. 《Journal of forensic sciences》2020,65(2):597-600
As DNA technology becomes increasingly sensitive, forensic laboratories are receiving more low-template DNA samples. These samples, already low in DNA content, become even more challenging to process as the available DNA becomes further reduced during the extraction step. In this study, two extraction modifications were tested to determine if the cause of DNA loss could be identified and mitigated. A double lysis technique was used to test for DNA loss in the sample collection substrate, and lysate eluates were re-extracted to determine DNA loss from inefficient binding to the silica column. Both modifications showed DNA was lost at these steps. However, resulting STR profiles from these samples had fewer peaks and lower peak heights when compared to samples processed with no extraction modifications. Overall, the potential benefits of adding these extraction modifications for low-template DNA sample processing are not enough to justify the risk associated with additional manipulation. 相似文献
886.
《Science & justice》2020,60(3):253-262
Papaver somniferum, commonly known as opium poppy, is the source of natural opiates, which are used as analgesics or as precursors in the creation of semi-synthetic opioids such as heroin. An increase in opioid addiction in the United States has resulted in high rates of illicit opioid use and overdoses. It has recently been shown that P. somniferum DNA suitable for genetic analysis can be recovered from heroin samples. The development of a comprehensive genetic individualization tool for opium poppy could serve to link cases and strengthen programs such as the Drug Enforcement Administration’s (DEA) Heroin Signature Program, which seeks to combat rising opioid use.The purpose of this study was to develop a quantitative real-time PCR (qPCR) method for the quantification of opium poppy DNA, compare three commercial DNA extraction kits for their ability to isolate DNA from poppy seeds, and evaluate nineteen opium poppy short tandem repeat (STR) markers for their use in a forensic identification panel. Such a panel could be used for individualizing samples and determining the geographic origin in heroin or poppy seed tea cases. The qPCR method was proven to be reproducible and reliable, specific for P. somniferum, and sensitive enough for forensic case-type samples. Of the three kits tested, the nexttec™ one-step DNA Isolation Kit for Plants was the optimal method and facilitated rapid extraction of DNA from poppy seeds. The majority of evaluated STR primer sets were unreliable or had low discriminatory power, limiting their use for individualization of poppy samples. A six-locus STR multiplex was developed and evaluated according to Scientific Working Group on DNA Analysis Methods (SWGDAM) and International Society of Forensic Genetics (ISFG) guidelines, including the use of a sequenced allelic ladder. The multiplex was found to have low discriminatory power, with greater than two-thirds of samples analyzed having just two different genotypes. The multiplex was determined to be unsuitable for individualization; however, a genotype map was developed as a proof of concept that these markers may be useful for determining the biogeographical origin of samples. Searching the poppy genome for new STR markers and developing new primer sets may be necessary for the creation of a powerful genetic tool for the individualization of P. somniferum. 相似文献
887.
The regulatory HERC2 SNP, rs12913832, is strongly associated with blue and brown eye colour. However, eye colour in heterozygous rs12913832 individuals is observed to vary greatly. Missense mutations in OCA2, such as rs1800407 and rs74653330, are associated with lighter eye colour in some but not all heterozygous rs12913832 individuals. Determining the physical linkage of these variants might help to further explain eye colour variation. So far, experimental haplotyping of these variants has been challenging because the genomic distance between them (∼ 135 kb) exceeds the fragment lengths produced by commonly used DNA isolation kits. The aim for this study was to explore novel methods for long distance haplotyping to assess associations between OCA2-HERC2 haplotypes and eye colour. DNA was isolated from frozen blood samples collected from Norwegians that are known to be heterozygous for both HERC2 rs12913832 and OCA2 SNPs, either rs1800407 (n = 23) or rs74653330 (n = 17), using the newly commercially available Monarch® HMW (heigh molecular weight) DNA Extraction Kit (New England BioLabsinc). We successfully isolated DNA fragments up to 210 kb, which were long enough to haplotype OCA2-HERC2 loci by droplet digital PCR (ddPCR). Three haplotypes were observed in the study population: rs12913832:A-rs1800407:T in 22/23 individuals, rs12913832:A-rs1800407:C in 1/23 individuals and rs12913832:A-rs74653330:T in 16/16 individuals. As expected, all individuals with the rs12913832:A-rs74653330:T haplotype had intermediate to blue eye colour. However, the rs12913832:A-rs1800407:T haplotype was observed in both blue and brown-eyed individuals, suggesting more research is needed. 相似文献
888.
Latent DNA detection has the potential to transform aspects of DNA collection at scenes and from items. In the absence of being able to visualise the location of cellular material, all collection of samples at crime scenes is currently performed blind. With the advent of the application of a nucleic acid staining dye, the DNA within skin cells (commonly called keratinocytes and corneocytes) can be visualised. Diamond Dye fluoresces when it binds to the backbone of DNA. This fluorescence can be recorded using a simple mini-microscope allowing the location and number of cells to be recorded. The potential to visualise cells on a wide range of substrates opens the possibility to target sample collection and to triage samples for further analyses to only those containing DNA. Diamond Dye has been found to be safe at the concentration used, inexpensive, available commercially, easy to apply, is highly sensitive, and does not inhibit further analyses such as PCR. This work presented at the ISFG congress gives an overview of the current developments on using DNA staining dyes to record the number of cells present on a wide range of substrates. It is essential to firstly understand the composition of cellular material deposited by touch, where it originates and the relative composition of corneocytes and cell-free DNA. Insight into the origins of touch DNA will be presented along with the staining of nuclei using a range of dyes to show corneocyte degradation. The presentation will cover how DNA binding dyes can be used to effectively triage sample collection, monitor cell collection using different swabs and tapes. 相似文献
889.
Currently, there are approximately 750 unidentified human remains and 2500 long-term missing persons in Australia. The Australian Federal Police National DNA Program for Unidentified and Missing Persons (Program) is using a multifaceted, multijurisdictional, multiagency, and multidisciplinary approach in a dedicated effort to identify these unknown deceased persons, scientifically link them to known missing persons, and provide answers to their families. The nationally coordinated Program provides its police, forensic, and coronial stakeholders with a suite of contemporary forensic technologies, databases, and experts to forensically examine the skeletonised remains and recover post-mortem data for comparison to the available ante-mortem data for each missing person. Through a number of physical and virtual public outreach activities, families with missing relatives have been encouraged to provide vital ante-mortem forensic information, records, and samples to aid the identification process. To date, this unique Program has assisted to resolve a number of unidentified and missing persons cases from both historical and contemporary contexts, using a combination of genetic and non-genetic techniques, and local and national databases. The centralisation of Program capabilities, expertise, and resources to conduct this type of unique and challenging casework is proving to be the most effective and efficient way to generate investigative leads, identify human remains, and resolve long-term missing persons cases in Australia. 相似文献
890.
On November 13, 1985 at 9:20 p.m., the Nevado del Ruiz Volcano erupted (A Glacier Snowy Volcano 17457 fts above sea level). The lahar, melting ice and landslide devastated the town of Armero located 45 kilometers away in a matter of minutes, in the Tolima department of Colombia. More than 25,000 people died or were reported missing. This tragedy is the largest natural disaster to date in Colombia. The Armando Armero Foundation is a Non-Governmental Organization (NGO) that brings together survivors of this tragedy. This NGO is making efforts to reunite families in association with Servicios Médicos Yunis Turbay y Cia. Different strategies are used to search and find matches in our database, including documents and records, autosomic STR, Y chromosome STR and mtDNA analysis. Thus far, four families have been reunited in this process. 相似文献