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991.
The aim of this study is to provide an overview of ongoing research on and the development of identification tools for big cats (Panthera tigris, Panthera leo, Panthera pardus, …). The set of tools includes a species-specific RTPCR quantitation system (nuclear and mitochondrial), STR multiplexes, a rapid system for big cat species determination, and a database solution. 相似文献
992.
Carolyn A. Lewis B.S. Tiffany R. Layne M.S. Sarah J. Seashols‐Williams Ph.D. 《Journal of forensic sciences》2019,64(6):1823-1830
Molecular‐based approaches for biological source identification are of great interest in the forensic community because of a lack of sensitivity and specificity in current methods. MicroRNAs (miRNAs) have been considered due to their robust nature and tissue specificity; however, analysis requires a separate RNA extraction, requiring an additional step in the forensic analysis workflow. The purpose of this study was to evaluate miRNA detection in blood, semen, and saliva using DNA extraction methods commonly utilized for forensic casework. RT‐qPCR analysis revealed that the tested miRNAs were consistently detectable across most tested DNA extraction methods, but detection was significantly reduced compared to RNA extracts in some biological fluids. DNase treatment was not necessary to achieve miRNA‐specific results. A previously developed miRNA panel for forensic body fluid identification was evaluated using DNA extracts, and largely demonstrated concordance with results from samples deriving from RNA extracts of semen, blood, and saliva. 相似文献
993.
Pregnancies, including ones that follow sexual assaults, occasionally produce hydatidiform moles. The alleged fathers (AFs) of moles have been tested for paternity by identifying the mole's locus phenotype—the one or two visible paternal obligate alleles (POAs) per locus. The probability that the mole inherited the POAs from the AF was divided by the probability that the mole inherited the POAs from a random man. This likelihood ratio (LR) would increase if the mole's specific genotype was known. Moles are generated in five different ways that produce five distinct genotypes. Examining a mole's multilocus STR profile reveals a mole's pathogenesis, determines locus genotypes, and increases paternity LRs. 相似文献
994.
Hongzhi Huang Xiaozhao Liu Juanbo Cheng Linxia Xu Ximiao He Chao Xiao Daixin Huang Shaohua Yi 《Journal of forensic sciences》2022,67(1):136-148
Identifying the source of body fluids found at a crime scene is an essential forensic step. Some methods based on DNA methylation played significant role in body fluids identification. Since DNA methylation is related to multiple factors, such as race, age, and diseases, it is necessary to know the methylation profile of a given population. In this study, we tested 19 body fluid-specific methylation markers in a Chinese Han population. A novel multiplex assay system based on the selected markers with smaller variation in methylation and stronger tissue-specific methylation were developed for the identification of body fluids. The multiplex assay were tested in 265 body fluid samples. A random forest model was established to predict the tissue source based on the methylation data of the 10 markers. The multiplex assay was evaluated by testing the sensitivity, the mixtures, and old samples. For the result, the novel multiplex assay based on 10 selected methylation markers presented good methylation profiles in all tested samples. The random forest model worked extremely well in predicting the source of body fluids, with an accuracy of 100% and 97.5% in training data and test data, respectively. The multiplex assay could accurately predict the tissue source from 0.5 ng genomic DNA, six-months-old samples and distinguish the minor component from a mixture of two components. Our results indicated that the methylation multiplex assay and the random forest model could provide a convenient tool for forensic practitioners in body fluid identification. 相似文献
995.
Population: Population samples for gene diversity studies were obtained from the Virginia Division of Forensic Science (bloodstains), Richmond, VA. Ninety-eight Caucasian and 100 African American samples were included in this study. 相似文献
996.
Mendes-Junior CT Ferreira LB Canas Mdo C Pimentel AL Muniz YC Wiezel CE Heckmann MI Luizon MR Sousa SM Simões AL 《Journal of forensic sciences》2007,52(2):495-497
Population: Unrelated males from the S?o Paulo State, Brazil (n=617). 相似文献
997.
Population: Eighty male individuals from a nomadic tribal population belonging to Dravidian and Indo-Caucasian ethnicities from Deccan Plateau, Andhra Pradesh, India, were analyzed in the present study. 相似文献
998.
Norris JV Manning K Linke SJ Ferrance JP Landers JP 《Journal of forensic sciences》2007,52(4):800-805
This report focuses on the development of a method for chemically induced enhancement of cell elution and recovery from cotton swabs. The method exploits the exclusive use of detergents for intact cell removal, and can be utilized in conjunction with, or to circumvent, conventional differential extraction (DE). Samples treated with Sarkosyl (54.4 +/- 1.8%) and sodium dodecyl sulfate (SDS) (78.5 +/- 0.7%) yielded higher sperm cell recoveries than a conventional DE buffer (39.4 +/- 2.1%). The results indicated that the choice of detergent affected sperm cell yield, with anionic detergents having the greatest effect. Storage time of samples affected the concentration of detergent required for optimal sperm cell recovery, longer times requiring increased detergent concentrations. In addition, the extent of sperm cell lysis by proteinase K digestion was evaluated. The results indicate that the exclusive use of SDS enhances the release of sperm and epithelial cells from a cotton swab as compared with DE buffer, providing for a more effective DNA analysis. 相似文献
999.
Laza D Nys B Kinder JD Kirsch-De Mesmaeker A Moucheron C 《Journal of forensic sciences》2007,52(4):842-850
In traditional scanning electron microscopy/energy dispersive X-ray analysis of gunshot residue (GSR), one has to cope more and more frequently with limitations of this technique due to the use of lead-free ammunition or ammunition lacking heavy metals. New methods for the analysis of the organic components of common propellant powder stabilizers were developed based on liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS). A multiple reactions monitoring scanning method was created for the screening of akardite II, ethylcentralite, diphenylamine, methylcentralite, N-nitrosodiphenylamine, 2-nitrodiphenylamine, and 4-nitrodiphenylamine, present in standards mixtures. Five out of seven of these target compounds can be selectively identified and distinguished from the two others with a high accuracy. Samples from the hands of a shooter were collected by swabbing and underwent solid phase extraction prior to analysis. Detection limits ranging from 5 to 115 mug injected were achieved. Results from several firing trials show that the LC-MS/MS method is suitable for the detection of stabilizers in samples collected following the firing of 9 mm Para ammunitions. 相似文献
1000.