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Through the analysis of DNA extracted from the gut contents of larvae known to consume human tissue, a methodology emerges for determining the source of their sustenance. In this study, human liver was provided as a food source to larvae and adults of Calliphora vicina Robineau-Desvoidy (Diptera: Calliphoridae). Emphasis was primarily placed on evaluating the quality and persistence of human genetic material present in the gut of larvae as well as in the secretions of adults that emerged from larvae fed on human liver. The findings revealed that viable genetic material appropriate for human identification could be discerned only within the larvae gut, even after a two-hour fasting period. [ABSTRACT FROM AUTHOR]

Two probabilistic genotyping (PG) programs, STRMix™ and TrueAllele™, were used to assess the strength of the same item of DNA evidence in a federal criminal case, with strikingly different results. For STRMix, the reported likelihood ratio in favor of the non-contributor hypothesis was 24; for TrueAllele it ranged from 1.2 million to 16.7 million, depending on the reference population. This case report seeks to explain why the two programs produced different results and to consider what the difference tells us about the reliability and trustworthiness of these programs. It uses a locus-by-locus breakdown to trace the differing results to subtle differences in modeling parameters and methods, analytic thresholds, and mixture ratios, as well as TrueAllele's use of an ad hoc procedure for assigning LRs at some loci. These findings illustrate the extent to which PG analysis rests on a lattice of contestable assumptions, highlighting the importance of rigorous validation of PG programs using known-source test samples that closely replicate the characteristics of evidentiary samples. The article also points out misleading aspects of the way STRMix and TrueAllele results are routinely presented in reports and testimony and calls for clarification of forensic reporting standards to address those problems.

Introduction: Storage of specimens sampled from human remains for pathological testing, embalming for burial purposes, and for human identification often requires formalin fixation and/or paraffin embedding. Current knowledge in molecular biology techniques and forensic DNA analysis makes it possible to optimize the extraction of amplifiable DNA from formalin-fixed tissues by improving the pre-treatment, optimizing the digestion condition of proteinase K, simplifying the extraction protocol and purifying the extracted DNA with optimized volumes of alcohol. Aim: This research sought to extract amplifiable DNA from thirteen brain, bone marrow and cartilage samples from four formalin embalmed human cadavers. Materials and Methods: Brain, cartilage and bone marrow samples were taken from four different cadavers at autopsy at the Ghana Police Hospital mortuary in Accra, Ghana sixty-two days after embalming. An optimized preparation and DNA extraction protocol was carried out on all the samples. Brain samples were also taken from a non-formalin treated fifth cadaver of known STR profile, and standard DNA extraction performed to serve as positive control. Results: Our optimized protocol yielded detectable quantities of DNA from the samples when quantified with the 7500 Real-Time PCR equipment. The extracted DNA also yielded full STR profiles with varying peak heights for forensic identification purposes. The measured degradation indexes of the DNA samples were greater than 1.0, with peak heights of generated STR profiles above the limits of detection of the 3500 genetic analyzer. Conclusion: Our current study demonstrated an optimized method of DNA extraction from tissues (brain, cartilage and bone marrow) sampled from formalin embalmed human cadavers. The optimized protocol reduced the concentration of formalin fixation residues in extracted DNA from formalin-fixed tissues, thereby improving the amplification efficiency for STR profiling. Brain, bone marrow and cartilages can be a good source of DNA from embalmed and degraded human remains, though for skeletonized human remains together with teeth and long bones. [ABSTRACT FROM AUTHOR]

The use of mesenchymal stem cells (MSCs) with a pronounced immunomodulatory activity is a promising trend in the development of biomedical cell preparations (BMCPs). In oncohematology, the use of BMCPs containing MSCs is aimed at supporting hematopoiesis after cotransplantation with hematopoietic stem cells (HSC) and suppressing immune conflicts in allogeneic unrelated transplantation and severe autoimmune processes. An obligatory step in BMCP registration consists in confirmation of the MSCs' authenticity, which includes the establishment of morphological characteristics, the assessment of the expression of specific markers and proteins, and confirmation of the cell genetic stability during cultivation. Determination of genetic-stability markers is possible using various methods; however, according to the recommendations of the American National Standardization Institute, the standard is the analysis of short tandem repeats (STR analysis). The purpose of this study is to develop the algorithm for determining the authenticity of BMCPs containing MSCs including STR analysis. MSCs were identified in BMCPs on the basis of the presence of immunological markers and spindle-cell adhesion to plastic. The number of viable cells was counted with a Goryaev's chamber. Immunophenotypic characteristics of MSCs were assessed by flow cytometry. The level of production of specific proteins was assayed with enzyme immunoassay. Markers of genetic stability were identified by STR analysis. The methods were tested in triplicate for ten BMCP samples to confirm the reproducibility and reliability of the results. The algorithm developed for determining the BMCP authenticity has a high accuracy, as it includes the STR analysis technique, which makes it possible to identify 19 polymorphic STR markers located on different alleles. Using this method will allow BMCP manufacturers to pass the procedure of state registration of drugs. [ABSTRACT FROM AUTHOR]

Epithelioid trophoblastic tumor (ETT) is a rare neoplasm derived from chorionic intermediate trophoblast cells, representing less than 2% of all gestational trophoblastic neoplasms. Classically, ETT presents as a uterine mass in women of reproductive age following a term pregnancy. The time from pregnancy to tumor development varies from months to several years. ETT most often arises in the endometrium, followed by the cervix. Extrauterine ETT are extremely infrequent, with few cases reported in the literature. We report a case of a 41-year-old woman, with history of three term pregnancies who presented with abdominal pain and elevated beta human chorionic gonadotropin (β-hCG) level, ten years after her last pregnancy. Imaging reported a 3.5 cm adnexal mass, suspicious for ectopic pregnancy. Hysterectomy and mass resection revealed a 4.7 cm, tan-yellow, necrotic mass adjacent to the broad ligament. Histologic evaluation in conjunction with immunohistochemical stains revealed a tumor consistent with ETT. No connection to the endometrium was found grossly or microscopically. DNA fingerprinting analysis revealed the tumor to have two copies of paternal alleles, as seen in molar gestations. One of the primary differential diagnoses for ETT is squamous cell carcinoma due to similar morphologic features. In challenging cases, genetic analysis demonstrating paternally derived genes can establish the diagnosis. In this report, we discuss the challenges in the diagnosis of extrauterine ETT, due to its rarity and highly variable presentation, given that appropriate diagnosis is critical for correct patient management. [ABSTRACT FROM AUTHOR]

The use of mesenchymal stem cells (MSCs), which have a pronounced immunomodulatory activity, is a promising direction in the development of biomedical cell preparations (BMCPs). In oncohematology, the use of BMCPs containing MSCs is aimed at supporting hematopoiesis during cotransplantation with hematopoietic stem cells (HSCs) and suppressing immune conflicts during allogeneic unrelated transplantation and severe autoimmune processes. An obligatory stage of registration of BMCPs is confirmation of the identity of the MSC cell line (CL), which includes the establishment of morphological characteristics, evaluation of the expression of specific markers and proteins, and confirmation of the genetic stability of CL during cultivation. Determination of markers of genetic stability is possible using various methods, however, according to the recommendations of the American National Standardization Institute, the standard is the analysis of short tandem repeats (STR analysis). The purpose of the study is to develop an algorithm for determining the authenticity of BMCPs containing MSCs, including STR analysis. Material and methods. Identification of MSC cells in BMCP was performed according to the criteria of the International Society for Cell Therapy. Viable cells were counted in a Goryaev chamber. Immunophenotypic characteristics of MSCs were determined by flow cytometry. The level of production of specific proteins was assessed using enzyme immunoassay. Genetic stability markers were identified by STR analysis. Results and discussion. The methods were tested in triplicate for ten BMCP samples to confirm the reproducibility and reliability of the results. The developed algorithm for determining the authenticity of BMCP has a high accuracy, as it includes the STR analysis technique, which makes it possible to identify 19 polymorphic STR markers located on different alleles. Using the method will allow BMCP manufacturers to go through the procedure of state registration of drugs.

Touch DNA has become increasingly important evidence in todays' forensic casework. However, due to its invisible nature and typically minute amounts of DNA, the collection of biological material from touched objects remains a particular challenge that underscores the importance of the best collection methods for maximum recovery efficiency. So far, swabs moistened with water are often utilized in forensic crime scene investigations for touch DNA sampling, even though an aqueous solution provokes osmosis, endangering the cell's integrity. The aim of the research presented here was to systematically determine whether DNA recovery from touched glass items can be significantly increased by varying swabbing solutions and volumes compared with water‐moistened swabs and dry swabbing. A second objective was to investigate the possible effects of storage of swab solutions prior to genetic analysis on DNA yield and profile quality when stored for 3 and 12 months, as is often the case with crime scene samples. Overall, the results indicate that adapting volumes of the sampling solutions had no significant effect on DNA yield, while the detergent‐based solutions performed better than water and dry removal, with the SDS reagent yielding statistically significant results. Further, stored samples showed an increase in degradation indices for all solutions tested, but no deterioration in DNA content and profile quality, allowing for unrestricted processing of touch DNA samples stored for at least 12 months. One further finding was a strong intraindividual change in DNA amounts observed over the 23 deposition days which may be related to the donor's menstrual cycle. [ABSTRACT FROM AUTHOR]

Introduction: Storage of specimens sampled from human remains for pathological testing, embalming for burial purposes, and for human identification often requires formalin fixation and/or paraffin embedding. Current knowledge in molecular biology techniques and forensic DNA analysis makes it possible to optimize the extraction of amplifiable DNA from formalin-fixed tissues by improving the pre-treatment, optimizing the digestion condition of proteinase K, simplifying the extraction protocol and purifying the extracted DNA with optimized volumes of alcohol. Aim: This research sought to extract amplifiable DNA from thirteen brain, bone marrow and cartilage samples from four formalin embalmed human cadavers. Materials and Methods: Brain, cartilage and bone marrow samples were taken from four different cadavers at autopsy at the Ghana Police Hospital mortuary in Accra, Ghana sixty-two days after embalming. An optimized preparation and DNA extraction protocol was carried out on all the samples. Brain samples were also taken from a non-formalin treated fifth cadaver of known STR profile, and standard DNA extraction performed to serve as positive control. Results: Our optimized protocol yielded detectable quantities of DNA from the samples when quantified with the 7500 Real-Time PCR equipment. The extracted DNA also yielded full STR profiles with varying peak heights for forensic identification purposes. The measured degradation indexes of the DNA samples were greater than 1.0, with peak heights of generated STR profiles above the limits of detection of the 3500 genetic analyzer. Conclusion: Our current study demonstrated an optimized method of DNA extraction from tissues (brain, cartilage and bone marrow) sampled from formalin embalmed human cadavers. The optimized protocol reduced the concentration of formalin fixation residues in extracted DNA from formalin-fixed tissues, thereby improving the amplification efficiency for STR profiling. Brain, bone marrow and cartilages can be a good source of DNA from embalmed and degraded human remains, though for skeletonized human remains together with teeth and long bones.

Abstract Background Forensic DNA analysis is one of the most advanced tools in the criminal investigation. It is used successfully in solving offenses involving rape, paternity disputes, murder or attempt to murder, and dacoity as well as identification of mutilated body remains. DNA profiling is used to determine paternity in sexual offense cases where abortion takes place and the product of conception can be anywhere from 6 to 10 weeks of gestation to 8 months. In the present case, a tissue sample stated as a vesicular mole and blood samples of the mother and suspected father were submitted to the DNA division of our laboratory for paternity analysis. Results Genotyping results revealed a single allele at all the tested short tandem repeat (STR) loci. The allele obtained at each locus was common with the suspected father. Such type of genotype was very rare and not observed earlier; therefore, repeated analysis was done and the same genotype was obtained every time. DNA profiling revealed all the alleles in the vesicular mole to be of paternal origin only, devoid of any maternal alleles. After referring to books on gynecology, it was confirmed that the genotype obtained was of hydatidiform mole. Conclusions In this POCSO Act case, the product of conception (about 1.5 months old) was termed a vesicular mole, and blood samples of the mother and suspected father were sent for the DNA paternity test. STR profiling of the product of conception sample displayed no maternal tissue contamination and non-inheritance of maternal alleles, showing the case to be of molar pregnancy also called hydatidiform mole, a very rare phenomenon in the forensic scenario. After thorough analysis, the case was reported and it was the first of its kind to be reported in a forensic laboratory in Maharashtra, India.

Every week, 1–2 breeds of farm animals, including local cattle, disappear in the world. As the keepers of rare allelic variants, native breeds potentially expand the range of genetic solutions to possible problems of the future, which means that the study of the genetic structure of these breeds is an urgent task. Providing nomadic herders with valuable resources necessary for life, domestic yaks have also become an important object of study. In order to determine the population genetic characteristics, and clarify the phylogenetic relationships of modern representatives of 155 cattle populations from different regions of the world, we collected a large set of STR data (10,250 individuals), including unique native cattle, 12 yak populations from Russia, Mongolia and Kyrgyzstan, as well as zebu breeds. Estimation of main population genetic parameters, phylogenetic analysis, principal component analysis and Bayesian cluster analysis allowed us to refine genetic structure and provided insights in relationships of native populations, transboundary breeds and populations of domestic yak. Our results can find practical application in conservation programs of endangered breeds, as well as become the basis for future fundamental research. [ABSTRACT FROM AUTHOR]

Background: Forensic DNA analysis is one of the most advanced tools in the criminal investigation. It is used successfully in solving offenses involving rape, paternity disputes, murder or attempt to murder, and dacoity as well as identification of mutilated body remains. DNA profiling is used to determine paternity in sexual offense cases where abortion takes place and the product of conception can be anywhere from 6 to 10 weeks of gestation to 8 months. In the present case, a tissue sample stated as a vesicular mole and blood samples of the mother and suspected father were submitted to the DNA division of our laboratory for paternity analysis. Results: Genotyping results revealed a single allele at all the tested short tandem repeat (STR) loci. The allele obtained at each locus was common with the suspected father. Such type of genotype was very rare and not observed earlier; therefore, repeated analysis was done and the same genotype was obtained every time. DNA profiling revealed all the alleles in the vesicular mole to be of paternal origin only, devoid of any maternal alleles. After referring to books on gynecology, it was confirmed that the genotype obtained was of hydatidiform mole. Conclusions: In this POCSO Act case, the product of conception (about 1.5 months old) was termed a vesicular mole, and blood samples of the mother and suspected father were sent for the DNA paternity test. STR profiling of the product of conception sample displayed no maternal tissue contamination and non-inheritance of maternal alleles, showing the case to be of molar pregnancy also called hydatidiform mole, a very rare phenomenon in the forensic scenario. After thorough analysis, the case was reported and it was the first of its kind to be reported in a forensic laboratory in Maharashtra, India. [ABSTRACT FROM AUTHOR]

Mixed human deoxyribonucleic acid (DNA) samples present one of the most challenging pieces of evidence that a forensic analyst can encounter. When multiple contributors, stochastic amplification, and allele drop-out further complicate the mixture profile, interpretation by hand becomes unreliable and statistical analysis problematic. Probabilistic genotyping software has provided a tool to address complex mixture interpretation and provide likelihood ratios for defined sets of propositions. The MaSTR™ software is a fully continuous probabilistic system that considers a wide range of STR profile data to provide likelihood ratios on DNA mixtures. Mixtures with two to five contributors and a range of component ratios and allele peak heights were created to test the validity of MaSTR™ with data similar to real casework. Over 280 different mixed DNA profiles were used to perform more than 2600 analyses using different sets of propositions and numbers of contributors. The results of the analyses demonstrated that MaSTR™ provided accurate and precise statistical data on DNA mixtures with up to five contributors, including minor contributors with stochastic amplification effects. Tests for both Type I and Type II errors were performed. The findings in this study support that MaSTR™ is a robust tool that meets the current standards for probabilistic genotyping. [ABSTRACT FROM AUTHOR]

We studied the genetic resistance to Campylobacter coli and Campylobacter jejuni in wild boar using both STR analysis and genome-wide association studies (GWAS). A total of 60 wild boars hunted in Tuscany (Italy) during the 2018/2019 hunting season were analyzed and genotyped. During postmortem operations, fecal swabs, liver samples and kidneys were collected. Two groups of animals were considered for the statistical analysis: 28 Campylobacter positive (22 for C. coli and 6 for C. jejuni) and 32 Campylobacter negative. Regarding STR analysis, 15 markers belonging to a marker panel validated by the International Society of Animal Genetics (ISAG) for swine were used: for each marker, alleles and genotype frequencies between the two groups of animals were compared using the Chi-square test and Fisher's exact tests. To analyze the genetic variability within groups, the following parameters were computed: molecular coancestry coefficients (fij), kinship distance (Dk), inbreeding coefficient (Fi), and genetic similarities (GS). The internal relatedness (IR) was also calculated, and ANOVA was used to verify the relationships between IR and Campylobacter groups. For GWAS, the Geneseek Genomic Profiler Porcine HD (70 k), containing 62,330 SNPs, was used. No differences in the internal relatedness (IR) were observed between the two groups (F = 5.64, P = 0.065) and no significant association between STRs and SNPs and Campylobacter positivity was observed. Although genetic resistance to bacterial diseases is often regulated by multiple genes controlling different processes of the host–pathogen interaction, in our studies no candidate genes that could be directly or indirectly involved in the development of the disease were identified. [ABSTRACT FROM AUTHOR]

Copyright of Rechtsmedizin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

DNA persistence and DNA transfer are important features in the assessment of a crime scene. The question how long DNA may persist at a certain location is similarly important as the one how the DNA has been transferred to this location. Depending on the source of the DNA as well as the conditions at the crime scene, the answer to this question is quite difficult. In this study, persistence of DNA from epithelial abrasions, blood cells, and saliva cells in indoor and outdoor scenarios has been investigated with regard to exposure time and exposure conditions including sunlight, temperature, and humidity in summer and winter scenarios. Overall, we generated 338 epithelial samples, 572 blood samples, and 572 saliva samples. A complete profile of the cell/DNA donor after exposure could be obtained in 47%, 65%, and 58% of epithelial abrasions, blood samples, and saliva samples, respectively. Regarding blood samples, there were no differences between supporting materials cloth and plastic; however, the percentage of complete profiles was higher for saliva samples on plastic and for epithelial samples on cloth. In indoor scenarios, complete profiles could be recovered from nearly all blood and saliva samples up to 9 months, whereas the amount of epithelial complete profiles already started to decline after 3 months. In outdoor scenarios, we observed a tipping point at an exposure time of 3 months. Blood and saliva samples collected after this period displayed complete profiles in less than 25% of samples. After 12 months, no outdoor sample showed a complete profile. The results of this study facilitate decisions on the relevance of recovered DNA from crime scenes. [ABSTRACT FROM AUTHOR]

Every week, 1–2 breeds of farm animals, including local cattle, disappear in the world. As the keepers of rare allelic variants, native breeds potentially expand the range of genetic solutions to possible problems of the future, which means that the study of the genetic structure of these breeds is an urgent task. Providing nomadic herders with valuable resources necessary for life, domestic yaks have also become an important object of study. In order to determine the population genetic characteristics, and clarify the phylogenetic relationships of modern representatives of 155 cattle populations from different regions of the world, we collected a large set of STR data (10,250 individuals), including unique native cattle, 12 yak populations from Russia, Mongolia and Kyrgyzstan, as well as zebu breeds. Estimation of main population genetic parameters, phylogenetic analysis, principal component analysis and Bayesian cluster analysis allowed us to refine genetic structure and provided insights in relationships of native populations, transboundary breeds and populations of domestic yak. Our results can find practical application in conservation programs of endangered breeds, as well as become the basis for future fundamental research.

Biological samples recovered from recipients of allogeneic haematopoietic stem cell transplant (HSCT) contain genetic material from both donor and him/herself. This chimeric condition can greatly complicate analysis of a DNA evidence and undermine its power of discrimination, as the specimens could be mistakenly identified as a mixed sample when in fact it originated from a single person. Profiling reference samples could help clarify the profile anomalies, however, the degree of mixture between host's and donor's genetic materials has been reported to vary depending on the tissue from which DNA were obtained. As a result, knowledge to select appropriate sources of reference samples that would most likely reveal the person's pre- and post-transplant alleles becomes necessary to minimise any possible misunderstanding during the subsequent DNA profile interpretation and comparison. This work investigated the extent of chimerism present in different types of biological samples collected from an individual who had undergone a bone marrow transplant as a child (post-transplant interval, PTI >28 years). DNA profiles from buccal cells, saliva, hair roots, and fingernail clippings were generated using AmpF ℓ STR™ Identifiler™ Plus/Direct PCR Amplification Kit. The donor's STR profile was used to identify donor- and host-specific alleles (DSA and HSA, respectively), and relative donor chimerism (%Ch) of each marker was calculated. Results showed that the saliva sample contained the highest level of chimerism, with complete profile of donor being detected and the mean %Ch was 34.0 ± 4.5. Four out of eight DSA dropped out from the buccal cell profile, and the mean %Ch was 24.2 ± 1.7. Hair roots and fingernail clippings yielded single source profiles and only host's original alleles were present. Except for the fingernail results, these observations agreed with many of the previous studies, which further demonstrated the need for raising awareness among forensic genetic laboratories regarding the type of reference samples that should be collected in future cases. [ABSTRACT FROM AUTHOR]

DNA fingerprinting analysis is used to solve cases of murder, rape, paternity, child swapping, immigration and many more. Sir Alec John Jeffry, also known as the Father of DNA Fingerprinting, first applied DNA profiling in the field of forensic science in the late 1980s. A case of disputed maternity was registered by Delhi Police. The victim of the case complained of missing her baby girl. After two months of investigation, it was found that about two months earlier a baby girl was found abandoned near a canal in the jurisdiction of another Police Station. After the direction of the Child Welfare Committee, doctors preserved the blood samples of the victim and the baby girl. Delhi Police deposited the preserved blood samples of the victim, and the baby girl at Forensic Science Laboratory, Rohini, Delhi for DNA Fingerprint Analysis to solve the case of disputed maternity. The DNA profiling performed on the blood samples of the victim and the baby girl confirmed that the victim is the biological mother of the abandoned baby girl and solved the disputed maternity case with absolute certainty. [ABSTRACT FROM AUTHOR]

Abstract Cat predation upon bat species has been reported to have significant effects on bat populations in both rural and urban areas. The majority of research in this area has focussed on observational data from bat rehabilitators documenting injuries, and cat owners, when domestic cats present prey. However, this has the potential to underestimate the number of bats killed or injured by cats. Here, we use forensic DNA analysis techniques to analyze swabs taken from injured bats in the United Kingdom, mainly including Pipistrellus pipistrellus (40 out of 72 specimens). Using quantitative PCR, cat DNA was found in two‐thirds of samples submitted by bat rehabilitators. Of these samples, short tandem repeat analysis produced partial DNA profiles for approximately one‐third of samples, which could be used to link predation events to individual cats. The use of genetic analysis can complement observational data and potentially provide additional information to give a more accurate estimation of cat predation.

The MinION nanopore sequencing device (Oxford Nanopore Technologies, Oxford, UK) is the smallest commercially available sequencer and can be used outside of conventional laboratories. The use of the MinION for forensic applications, however, is hindered by the high error rate of nanopore sequencing. One approach to solving this problem is to identify forensic genetic markers that can consistently be typed correctly based on nanopore sequencing. In this pilot study, we explored the use of nanopore sequencing for single nucleotide polymorphism (SNP) and short tandem repeat (STR) profiling using Verogen's (San Diego, CA, USA) ForenSeq DNA Signature Prep Kit. Thirty single-contributor samples and DNA standard material 2800 M were genotyped using the Illumina (San Diego, CA, USA) MiSeq FGx and MinION (with R9.4.1 flow cells) devices. With an optimized cutoff for allelic imbalance, all 94 identity-informative SNP loci could be genotyped reliably using the MinION device, with an overall accuracy of 99.958% (1 error among 2926 genotypes). STR typing was notably error prone, and its accuracy was locus dependent. We developed a custom-made bioinformatics workflow, and finally selected 13 autosomal STRs, 14 Y-STRs, and 4 X-STRs showing high consistency between nanopore and Illumina sequencing among the tested samples. These SNP and STR loci could be candidates for panel design for forensic analysis based on nanopore sequencing. [ABSTRACT FROM AUTHOR]

Over recent years, DNA profiling techniques have become highly sensitive. Even small amounts of DNA at crime scenes can be analysed leading to new defence strategies. At court, defence lawyers rarely question the existence of a DNA trace (source level) but challenge how the DNA was transferred to the scene (activity level). Nowadays, the most common defence strategy is to claim that somebody else had stolen the defendant's gloves and used them while breaking and entering. In this study we tested this statement. Using gloves made of different material (cloth, leather, rubber) and varying secondary transfer surfaces (wood, metal, glass), we simulated a few of the most likely transfer scenarios that occur during breaking and entering. While we detected the presence of DNA on the outside of 92 of the 98 gloves tested, we observed only one case of secondary transfer in a total of 81 transfer experiments. This data demonstrates that secondary transfer under conditions resembling realistic conditions is a very rare event. [ABSTRACT FROM AUTHOR]

Abstract Background To establish one primary cell line of human liver metastasis of colon cancer. Methods HCS1220 cell line was derived from one liver metastasis of colon cancer patient’s resected tumor sample. The characterization of the cell line was defined by karyotype analysis, short tandem repeat (STR) analysis and mycoplasma contamination. Subcutaneous injection 1 × 106 cells to four BALB/c nude mice, the viable tumors were developed and diagnosed (H&E staining). The expression of biomarkers CK20 and CDX2 for colon cancer were determined by immunocytochemistry assay. Results HCS1220 cell line can grow stably and continuously passage. During the grow process, the contact loss in the growth process and superimposed growth, which could be defined as proliferation of malignant tumor. Chromosome analysis revealed the cells derived from human female. The cells were not contaminated by mycoplasma. By immunohistochemistry, the cell line was proven to express the biomarkers of colon cancer CK20 and CDX2, while a-fetoprotein, hep-1 and glypican-3 were stained negative, which demonstrated that the HCS1220 cell line originating from the intestinal tissue. Conclusions HCS1220 cell line has the characteristics of primary human liver metastasis of colon cancer. The results of STR have genetically showed that cell line is original, which can provided cell materials for research in vitro and can also help for establishing the mechanism model of liver metastasis of colon cancer and preparing, screening and evaluating anti-tumor drugs.

DNA analysis has been widely used in the forensic field in order to contribute to identifying the perpetrator of a crime. Forensic investigation in sexual assaults usually focuses on locating and identifying biological fluids, followed by DNA analysis. The identification of certain compounds present in condoms can be useful to reconstruct the occurred event, especially in cases of sexual assaults where the DNA analysis did not show the presence of a male profile and where RNA analysis did not show the presence of sperm markers. Herein we describe the case of a woman reporting to be victim of sexual assault, who was not able to provide accurate information concerning the dynamics of the event; she remembered only forced penile–vaginal penetration by a single perpetrator. We performed short tandem repeat (STR) analyses and mRNA typing for forensic genetics testing on vaginal and rectal swabs collected on the victim, and Fourier‐transform infrared spectroscopy (FTIR) followed by chromatographic analyses for the detection of condom compounds on the same swabs. The STR analysis showed only the victim's genetic profile, and RNA analysis showed only the presence of vaginal and skin markers. In this situation, the identification of condom compounds residues on vaginal swabs became important as it complemented other collected evidences allowing the Court to reconstruct the events. A proposal of likelihood ratio (LR) calculation for the assessment of the weight of evidence in this case is described. [ABSTRACT FROM AUTHOR]

Cat predation upon bat species has been reported to have significant effects on bat populations in both rural and urban areas. The majority of research in this area has focussed on observational data from bat rehabilitators documenting injuries, and cat owners, when domestic cats present prey. However, this has the potential to underestimate the number of bats killed or injured by cats. Here, we use forensic DNA analysis techniques to analyze swabs taken from injured bats in the United Kingdom, mainly including Pipistrellus pipistrellus (40 out of 72 specimens). Using quantitative PCR, cat DNA was found in two‐thirds of samples submitted by bat rehabilitators. Of these samples, short tandem repeat analysis produced partial DNA profiles for approximately one‐third of samples, which could be used to link predation events to individual cats. The use of genetic analysis can complement observational data and potentially provide additional information to give a more accurate estimation of cat predation. [ABSTRACT FROM AUTHOR]

DNA isolation is a process used for isolation of DNA from different types of samples using a combination of physical and chemical methods. A comparative study is made to isolate DNA from 30 teeth samples with some pre PCR and post PCR modifications in the organic Phenol: Chloroform: isoamyl alcohol, Automate ExpressTM prepfiler BTA kit and QIAamp® DNA Investigator Kit. Our result showed significant results which will be helpful in short listing the array of these techniques. [ABSTRACT FROM AUTHOR]

Copyright of Rechtsmedizin is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The persistence of DNA on washed items as well as the DNA transfer has become a major subject of research in recent years, especially after the detectability of minor DNA traces was heavily increased by sensitive analysis methods. Nowadays, the attribution of a DNA trace to an individual is only rarely questioned, whereas the way of application of this DNA to an item is subject to much discussion and speculation. Additionally, the removal of DNA by cleaning or its possible persistence on an item despite a cleaning process are often important problems in court. The aim of this study was to investigate whether DNA traces (blood, saliva, epithelial cells) on different objects (knives, plates, glasses, and plastic lids) can persist on the surface despite cleaning by different methods like hand-washing or the use of a dishwasher. In total, 120 samples were collected from artificially constructed blood, saliva, and epithelial cell stains on objects with smooth surfaces after washing and analyzed by STR amplification. Samples taken after rinsing or hand-washing resulted mainly in complete DNA profiles (62.5% of samples), while cleaning in the dishwasher rendered almost everything completely DNA-free. Since in the hand-washing experiments a secondary transfer of DNA through the water could not be ruled out, additional transfer experiments were conducted with blood and saliva samples on plates. Here, a carryover of DNA traces could be demonstrated up to the fifth washed item. [ABSTRACT FROM AUTHOR]

Genetic identification of skeletal human remains is often realized by short tandem repeat (STR) genotyping of nuclear DNA. Dental DNA is preferred to DNA from bone for the better protection of the endogenous DNA. Especially if whole tooth grinding is intended to access the DNA, contaminations with exogenous DNA have to be avoided. The immersion of the tooth in sodium hypochlorite (NaOCl, known as bleach) is one common procedure to clean the outer surface from extraneous DNA and PCR inhibitors. To investigate the impact of bleaching on endogenous DNA and the decontamination success, 71 recently extracted teeth were differently treated with sodium hypochlorite (2.5 or 5.0% NaOCl for 30 or 60 s, 5.0% NaOCl for 10 min, and control group) in the beginning of the extraction process, whereas equally handled afterwards. Quantitative and qualitative evaluation of the extracted DNA was performed. There was a great variation for the DNA concentration of the extracts even within a group of the same NaOCl treatment. Complete DNA profiles from single persons with alleles for the 16 ESS (European Standard Set) STR loci were obtained for all regarded teeth. A statistically significant difference between the DNA yields of the treatment groups was not determined. Moreover, a negative effect of NaOCl (2.5% and 5.0%) on the DNA recovery could not be observed. Significant larger amounts of DNA were extracted from anterior teeth in contrast to posterior teeth. [ABSTRACT FROM AUTHOR]

Between 1990 and 2018, the Defense POW/MIA Accounting Agency submitted 2177 cranial elements and 1565 teeth to the Armed Forces Medical Examiner System—Armed Forces DNA Identification Laboratory for DNA testing. In an effort to identify missing United States service members, materials were recovered from wartime losses inclusive of World War II, the Korean War, and Southeast Asia. Using four different DNA extraction protocols, DNA testing was performed using mitochondrial DNA Sanger sequencing, modified AmpFlSTR® Yfiler™, AmpFlSTR® MiniFiler™, PowerPlex® Fusion, or Next Generation Sequencing. This paper aims to provide optimal strategies for the DNA testing of skeletonized cranial materials. Cranial elements produced the most consistent results in Sanger sequencing using an organic purification; however, teeth were most successful for the same platform with an inorganic purification. The inverse is true for STR testing of cranial bones. Of the cranial elements, the temporal provided the most consistent results. [ABSTRACT FROM AUTHOR]

This research evaluates the current DNA quantification (Quantifiler™ Trio, PowerQuant®, Investigator® Quantiplex® Pro and InnoQuant® HY Fast) and autosomal STRs amplification kits (GlobalFiler™, PowerPlex® Fusion 6 C, Investigator® 24Plex QS) using 62 degraded skeletal remains from armed conflicts (petrous bone, femur, tibia, and tooth) with several parameters (autosomal small, large, and male target, degradation index, probability of degradation, number of alleles above analytical threshold, number of alleles above stochastic threshold, RFU, peak height ratio, number of reportable loci). The best qPCR/autosomal STRs amplification tandem was determined by comparing quantification results by a DNA quantity estimation based on sample average RFU. InnoQuant® HY Fast was the most sensitive kit, and no significative differences were observed among amplification kits; however, Investigator® 24 Plex QS was found to be the most sensitive in our samples. That is why InnoQuant™ and Investigator® 24Plex QS were determined to be the best tandem. • Four qPCR and three autosomal STRs commercial kits performance is compared with 62 critical skeletal remains. • InnoQuant® HY Fast was found as the most sensitive kit. • The three autosomal STRs kits tested achieved similar results. • InnoQuant® HY Fast and Investigator® 24Plex were found as the best duo. [ABSTRACT FROM AUTHOR]

Introduction: Allogeneic hematopoietic stem cell transplantation (alloHSCT) is a curative approach for multiple hematologic diseases. The success of alloHSCT is evaluated by analyzing the proportion of living donor cells in blood and bone marrow samples of the recipient (chimerism analysis). To monitor the engrafted cells, donor's individual genetic markers are analyzed in peripheral blood and bone marrow samples, usually by using short tandem repeat (STR) analysis. An alternative method to measure chimerism is based on insertion and deletion markers (InDels) analyzed by digital droplet PCR (ddPCR); however, this approach is rarely evaluated in clinical practice. Methods: In this study, we examined the usefulness of ddPCR‐based chimerism analysis against the standard STR analysis in samples around day+30 after alloHSCT in clinical practice using peripheral blood and bone marrow samples. Results: The median absolute difference between ddPCR and STR analysis was 0.55% points for bone marrow chimerisms and 0.25% points for peripheral blood chimerisms, respectively, including variation in the range of maximum 2% for both methods. The results of every single sample gave the same clinical message. Conclusion: According to our data, chimerism analysis by ddPCR has an excellent correlation with STR‐based analyses. Due to its fast and easy applicability, the ddPCR technique is suitable for chimerism monitoring in clinical practice. [ABSTRACT FROM AUTHOR]

This paper provides a retrospective of the DNA analysis performed by the Armed Forces Medical Examiner–Armed Forces DNA Identification Laboratory between 1990 and 2018. Over 13,000 postcranial osseous materials, comprised of wartime losses from World War II, the Korean War, and South‐East Asia, were examined by the following: mitochondrial DNA sequencing, a modified AmpFlSTR® Yfiler™, AmpFlSTR® MiniFiler™, PowerPlex® Fusion, or NGS. Four different DNA extraction protocols were used: incomplete demineralization coupled with an organic purification; complete demineralization with an organic purification; complete demineralization with an inorganic purification using QIAquick PCR Purification Kit; and a protocol designed specifically for use with next‐generation sequencing. In general, complete demineralization coupled with an organic purification was the optimal extraction protocol for sequencing of mitochondrial DNA, regardless of the osseous element tested. For STR testing, demineralization paired with an inorganic purification provided optimum results, regardless of kit used or osseous element tested. [ABSTRACT FROM AUTHOR]

Chimerism in humans is defined as the presence of two genetically different cell lines within the same organism. It is usually an acquired condition that is restricted to certain tissues and can be explained by therapeutic interventions such as blood transfusion or the transplantation of allogenic hematopoietic cells. Implications of such patients for forensic DNA testing have been described in the literature. In some rare cases, true inherited chimerism is observed. This so called tetragametic chimerism occurs via the fertilization of the two ova by two spermatozoa, followed by the fusion of early embryos and the development of an organism with intermingled cell lines. Such examples have been found in mice and other mammalian species including humans. We describe a phenotypically normal woman in whom tetragametic chimerism (46,XX/46,XX) was unexpectedly identified by STR typing during routine DNA profiling. Cytogenetic analysis proved to be a valuable tool for both independent confirmation and direct visualization of the two coexisting cell lines. [ABSTRACT FROM AUTHOR]

DNA transfer in aqueous solutions as well as the persistence of DNA on washed items has become a major subject of research in recent years and is often a significant problem in court. Despite these approaches, the question about the "mobility" of DNA especially in capital offenses cannot be answered in every case, since a variety of scenarios for DNA transfer are possible. The aim of this study was to investigate whether DNA traces could be distributed by cleaning an object. For this purpose, a large table surface and fabric piece were artificially provided with skin contact traces and body fluids (saliva and blood) in two series of experiments and then wiped off with water or with soap water (218 samples in total). These experiments resulted in a clear "carry over" of DNA traces especially for body fluid samples (100% of blood samples and 75% of saliva samples led to a complete profile). The results could be confirmed in a second experimental set-up with 384 samples using different cleaning agents and more intense cleaning actions. Even small amounts of 5–10 μl body fluid led to complete profiles in around 45% of the samples, while 20 μl led to nearly 65% complete profiles. A strong impact of the amount of traces and the chosen surface could be demonstrated, while the active component of the cleaning agent seemed to be of less influence with the explicit exception of chloric agents which rendered almost everything completely DNA-free. In summary, a distribution of DNA traces by wiping or scrubbing an object could be clearly proven. [ABSTRACT FROM AUTHOR]

Objectives: The human salivary gland (HSG) cell line, labeled as a submandibular ductal cell line, is commonly used as in vitro models to study radiation therapy, Sjögren's syndrome, pleomorphic adenoma, mucocele, epithelial‐to‐mesenchymal transition, and epigenetics. However, the American Type Culture Collection (ATCC) has recently released a list of cross‐contaminated cell lines that included HSG. Despite this notice, some research laboratories still use HSG as a salivary cell model. Therefore, this study examined the authenticity of HSG sampled from three different laboratories. Methods: DNA was extracted from HSG and additional salivary cell lines (NS‐SV‐AC, NS‐SV‐DC, A253, HSY) and submitted for cell line authentication with short tandem repeat (STR) analysis. Results: All HSG samples had STR profiles indicating >80% match with HeLa in both the ATCC and Deutsche Sammlung von Mikroorganismen und Zellkulturen (DSMZ) databases. This confirmed that HSG sampled from three different laboratories and HSY shared a common ancestry (host) with HeLa, whereas NS‐SV‐AC, NS‐SV‐DC, and A253 had unique STR profiles. Conclusion: Short tandem repeat analysis revealed that HSG was contaminated by the HeLa cell line. Furthermore, because genotyping of the original HSG cell line was not performed during its establishment, it will be difficult to authenticate an uncontaminated sample of HSG. [ABSTRACT FROM AUTHOR]

The aim of this paper is to present the STRAND (STR AN imal D atabase) cloud expert system for non-human DNA analysis. The cloud expert system (CES) combines the cross-referenced registries of STR markers for different species and a DNA database for comparison of DNA profiles, with a repository of scientific papers and a dashboard for unpublished data, protocols, negative results and announcements related to animal DNA typing. [ABSTRACT FROM AUTHOR]

In Belgium, it is a general recommendation to collect swabs and rinses in rape cases. We evaluated the need of both prelevations for successful DNA analysis based on historical data. DNA concentrations and success rate of STR analysis of a total of 213 PSA positive rinses (including 29 anal and 184 vaginal rinses) and 256 PSA positive swabs (including 55 anal and 201 vaginal swabs) were compared. The study includes 154 cases where both a swab and a rinse were analysed simultaneously. Considering all vaginal and anal swabs and all rinses together, the median of the DNA concentration of DNA isolates of swabs is approximately 2.5 times higher than those of the DNA isolates of rinses. Moreover the success rate of obtaining an autosomal STR profile useful to identify the assailant is 72% for swabs versus 65% for rinses for the cases where both a swab and a rinse were examined simultaneously. In conclusion, swabs were found to have a higher DNA yield and a higher success rate of STR analysis for identifying the alleged assailant than rinses. [ABSTRACT FROM AUTHOR]

The choice of soft or hard tissues to be sampled in case of exhumation of corpses for identification purposes or family relationship testing is based on the degradation conditions of the corpse: the more the corpse is degraded, the less DNA is expected to be retrieved from soft tissue. Therefore, the choice of the "best" tissue samples usually falls on teeth and bones in these "difficult" cases, even though the DNA extraction procedure requires time and effort and it can often result in unexpected, negative results. We here present the results of a daily practice survey that shows that it is possible to obtain good results even on DNA extracted from tissues that appear to be less "appealing" to the examiner by performing "simple" corneal/scleral swabs along with cartilage. While DNA extracted from cartilage has been already described, to our knowledge there is no evidence of publications in the scientific literature dealing with cornea/sclera as a source of DNA in the forensic laboratory. The obtained results demonstrate that it may be advisable to consider other tissues which bear the potential of returning good profile results despite not appearing particularly useful and better control of contamination. [ABSTRACT FROM AUTHOR]

The aim of this work was to investigate the possibility of secondary and tertiary DNA transfer during laundry. The modes of transfer tested were mixed and separate laundry of worn and unworn garments in household and public washing machines. In addition, the possibility of a background DNA carry-over from a washing machine’s drum was investigated. In the mixed (worn and unworn garments washed together) laundry experiment, 22% of samples from new unworn socks with no traceable DNA prior to experiment produced DNA profiles post-laundry. In the tertiary DNA transfer experiment performed in a public washing machine (unworn garments only), no detectable DNA profiles were observed. Samples collected from the internal drum of 25 washing and drying machines did not produce detectable STR profiles. The implications of these results are discussed in the context of forensic DNA casework analysis.ᅟA real-life scenario of secondary DNA transfer between worn and unworn garments during machine washing has been evaluated. Experiments demonstrated this scenario is possible (22% of samples) and may in fact result in high quality DNA profiles. On the contrary, testing washing machine’s interior for deposition of biological material between separate washing cycles to serve as a mediator of tertiary DNA transfer resulted in no DNA profiles. [ABSTRACT FROM AUTHOR]

DNA traces on clothes of drowned bodies can provide important evidence for police investigations, especially in cases of suspected suicides or homicides. However, it is generally assumed that the water 'erodes' a large part of the DNA depending especially on the exposure time. In forensic casework, DNA of suspects could be found frequently on clothes of drowned bodies after hours, sometimes days of exposure to water. This study was conducted to attempt a general statement about the conditions under which sufficient DNA remains can be expected for molecular genetic analysis. For this purpose, different scenarios were designed including DNA from three to five people, different types of waters (tap, pond, bathtub and river) for various time periods, with higher water pressure, different temperature, and soapy water (bathtub). Epithelial cells and blood cells were mounted on cotton cloths, and the DNA left after exposure was analyzed using the Powerplex® ESX17fast kit. In the indoor experiments, complete profiles could be seen even after 10 min rinsing of clothes under the tap and after 1 week in the bathtub. Outdoors, the results differed considerably between summer and winter as well as between pond and river. The longest exposure time still resulting in a complete profile was 2 weeks for a sample with skin cells in the pond during winter. In summer, the time period for erasing the bulk of DNA was 4 hours regarding epithelial samples and more than 1 day for blood samples in pond and river environments. All in all, the results demonstrate that DNA could still be recovered from clothes exposed to water for more than 1 week. [ABSTRACT FROM AUTHOR]

The detection of DNA of a certain person on the inside of a piece of clothing involved in a crime scene is usually seen as confirmation that this person is the owner or bearer and therefore participated in this crime. However, besides the possibilities of secondary or even tertiary transfer of DNA, the accused often argues that he lent the garment to another person who by chance did not leave any DNA while committing the crime. Then, forensic genetic scientists have to answer the question how long DNA persists on an item used in daily routine and how long a piece of clothing must be worn to definitively leave detectable DNA behind. In an attempt to answer these questions, several scenarios with two or three individuals wearing the same sweatband for different time periods were set up. DNA left on the sweatbands was isolated, quantified, and then analyzed using the Powerplex® ESX17fast kit. The majority of samples displayed all alleles of both/all three wearers on the outside (67%) as well as on the inside (80%) of the sweatbands. In contrast, a single profile of the first wearer could only be found once among all 204 samples, a single profile of the second wearer in 7% of samples. Wearing the sweatband for only 10 min was enough to result in a complete profile of the second wearer in 79% of samples. So, it is highly unlikely to wear/use a piece of clothing for even a short period of time without leaving own DNA behind. [ABSTRACT FROM AUTHOR]

Objective: Since there is no effective curative treatment for Duchenne muscular dystrophy (DMD), prevention mostly depends on genetic counseling and prenatal diagnosis. About two-thirds of the affected patients have large deletions or duplications, which can be detected by multiplex ligation-dependent amplification (MLPA). The remaining cases include small mutations, which cannot be easily identified by routine techniques. In such cases, linkage analysis may be a useful tool for prenatal diagnosis. Here we compared results obtained from linkage using short tandem repeats (STRs) with those by MLPA and sequencing analysis. Materials and methods: Eight Vietnamese pregnant women at risk of having a baby with DMD and requesting prenatal diagnosis were recruited in this study. MLPA and direct sequencing were applied to screen large rearrangements and point mutations in the dystrophin gene in the DMD probands and the fetal samples. STR linkage was also performed to analyze fetal mutation status. Results: By MLPA and sequencing analysis, five DMD patients showed deletions of the dystrophin gene, and no deletions of exons were detected in seven amniotic fluid cell samples; one patient harbored the out-of-frame small deletion of exon 43, which was also found in the fetal sample of this family. STR analysis revealed the transmission of a mutant allele inside each family. Conclusion: Our results suggest that the combination of STR and MLPA could be a rapid, reliable, and affordable detection protocol for determination of the carrier's status and prenatal diagnosis of DMD in a developing country such as Vietnam.