Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 17 de 17
Filter
Add more filters










Publication year range
1.
Front Public Health ; 11: 1236558, 2023.
Article in English | MEDLINE | ID: mdl-37942251

ABSTRACT

Asbestos-related diseases still represent a major public health problem all over the world. Among them, malignant mesothelioma (MM) is a poor-prognosis cancer, arising from the serosal lining of the pleura, pericardium and peritoneum, triggered by asbestos exposure. Literature data suggest the key role of iron metabolism in the coating process leading to the formation of asbestos bodies, considered to be both protective and harmful. Two sample sets of individuals were taken into consideration, both residing in Broni or neighboring cities (Northwestern Italy) where an asbestos cement factory was active between 1932 and 1993. The present study aims to compare the frequency of six SNPs involved in iron trafficking, previously found to be related to protection/predisposition to MM after asbestos exposure, between 48 male subjects with documented asbestos exposure who died of MM and 48 male subjects who were exposed to asbestos but did not develop MM or other neoplastic respiratory diseases (Non-Mesothelioma Asbestos Exposed - NMAE). The same analysis was performed on 76 healthy male controls. The allelic and genotypic frequencies of a sub-group of 107 healthy Italian individuals contained in the 1000 genomes database were considered for comparison. PCR-multiplex amplification followed by SNaPshot mini-sequencing reaction was used. The findings presented in this study show that the allelic and genotypic frequencies for six SNP markers involved in iron metabolism/homeostasis and the modulation of tumor microenvironment are not significantly different between the two sample sets of MM and NMAE. Therefore, the SNPs here considered do not seem to be useful markers for individual susceptibility to mesothelioma. This finding is not in agreement with previous literature.


Subject(s)
Asbestos , Mesothelioma, Malignant , Mesothelioma , Occupational Exposure , Male , Humans , Polymorphism, Single Nucleotide , Mesothelioma/genetics , Asbestos/adverse effects , Iron/metabolism , Homeostasis , Tumor Microenvironment
2.
Genes (Basel) ; 14(4)2023 03 31.
Article in English | MEDLINE | ID: mdl-37107609

ABSTRACT

In this article, we describe multiple analytical strategies that were first developed for forensic purposes, on a set of three bone samples collected in 2011. We analyzed a single bone sample (patella) collected from the artificially mummified body of the Baron Pasquale Revoltella (1795-1869), as well two femurs which allegedly belonged to the Baron's mother (Domenica Privato Revoltella, 1775-1830). Likely due to the artificial mummification procedures, the inner part of the Baron's patella allowed the extraction of high-quality DNA yields, which were successfully used for PCR-CE and PCR-MPS typing of autosomal, Y-specific, and mitochondrial markers. The samples extracted from the trabecular inner part of the two femurs yielded no typing results by using the SNP identity panel, whereas the samples extracted from the compact cortical part of the same bone samples allowed genetic typing, even by the employment of PCR-CE technology. Altogether, 10/15 STR markers, 80/90 identity SNP markers, and HVR1, HVR2, and HVR3 regions of the mtDNA were successfully typed from the Baron's mother's remains by the combined use of PCR-CE and PCR-MPS technologies. The kinship analysis showed a likelihood ratio of at least 9.1 × 106 (corresponding to a probability of maternity of 99.9999999%), and thus confirmed the identity of the skeletal remains as those of the Baron's mother. This casework represented a challenging trial for testing forensic protocols on aged bones samples. It highlighted the importance of accurately sampling from the long bones, and that DNA degradation is not blocked by freezing at -80 °C.


Subject(s)
DNA Fingerprinting , Forensic Genetics , Pregnancy , Humans , Female , Aged , Forensic Genetics/methods , DNA Fingerprinting/methods , DNA, Mitochondrial/genetics , Polymerase Chain Reaction , Body Remains
3.
Int J Legal Med ; 137(1): 145-156, 2023 Jan.
Article in English | MEDLINE | ID: mdl-35277774

ABSTRACT

Europe is turning a blind eye on a humanitarian disaster unfolding at its doorsteps, with thousands of migrants dying unidentified in Mediterranean waters. Since 2014, Italy has been struggling in an almost indifferent international scenario to identify its dead migrants. Despite the lack of sufficient resources, of the difficulties in collecting post mortem data from the disseminated bodies, and of the problems of contacting and collecting ante mortem information from relatives, it has been proven, with a series of pilot studies, that not only can these bodies be identified but that relatives are also looking for their loved ones and need death certificates. This article focuses on the administrative limbo and lack of regulations obliging single states to engage in appropriate procedures to maximise identification.


Subject(s)
Disasters , Transients and Migrants , Humans , Autopsy , Italy , Europe
4.
Biology (Basel) ; 11(8)2022 Aug 10.
Article in English | MEDLINE | ID: mdl-36009828

ABSTRACT

Although not without subjectivity, the cranial trait scoring method is an easy visual method routinely used by forensic anthropologists in sex estimation. The revision presented by Walker in 2008 has introduced predictive models with good accuracies in the original populations. However, such models may lead to unsatisfactory performances when applied to populations that are different from the original. Therefore, this study aimed to test the sex predictive equations reported by Walker on a contemporary Italian population (177 individuals) in order to evaluate the reliability of the method and to identify potential sexual dimorphic differences between American and Italian individuals. In order to provide new reference data to be used by forensic experts dealing with human remains of modern/contemporary individuals from this geographical area, we designed logistic regression models specific to our population, whose accuracy was evaluated on a validation sample from the same population. In particular, we fitted logistic regression models for all possible combinations of the five cranial morphological traits (i.e., nuchal crest, mastoid process, orbital margin, glabella, and mental eminence). This approach provided a comprehensive set of population-specific equations that can be used in forensic contexts where crania might be retrieved with severe taphonomic damages, thus limiting the application of the method only to a few morphological features. The results proved once again that the effects of secular changes and biogeographic ancestry on sexual dimorphism of cranial morphological traits are remarkable, as highlighted by the low accuracy (from 56% to 78%) of the six Walker's equations when applied to our female sample. Among our fitted models, the one including the glabella and mastoid process was the most accurate since these features are more sexually dimorphic in our population. Finally, our models proved to have high predictive performances in both training and validation samples, with accuracy percentages up to 91.7% for Italian females, which represents a significant success in minimizing the potential misclassifications in real forensic scenarios.

5.
Forensic Sci Int ; 340: 111421, 2022 Nov.
Article in English | MEDLINE | ID: mdl-36029719

ABSTRACT

In April 2015, a fishing boat that departed from Libya with about 1,000 migrants on board sank in the Mediterranean Sea. Most of the migrants were packed in the hull of the boat and drowned in the shipwreck. After fifteen months, the ship was recovered from the seabed and brought to a Sicilian naval area for forensic investigations. Skeletal remains belonging to more than 700 people were retrieved. A selected sample composed of 80 victims was considered in order to evaluate the possibility of achieving genetic profiles useful for a positive identification from these challenging specimens. The molecular features of the DNA recovered from a significant number of real casework samples exposed to seawater for long periods of time were described for the first time. Three different DNA extraction protocols and three different commercial kits were employed in order to generate genetic profiles based on the characterization of 21 autosomal STR loci. The combination of multiple DNA extractions and the cross-checking of multiple PCR amplifications with different kits allowed to obtain reliable genetic profiles characterized by at least 16 STR markers in more than 70% of the samples. The factors that could have affected the different quality of the genetic profiles were investigated and the bone preservation was examined through microscopic and macroscopic analyses. The approach presented in this study could be useful in the management of the genetic analysis of bone samples collected in other similar DVI scenarios. The genetic profiles recovered from the bone samples will be compared in kinship analysis to putative relatives of the victims collected in Africa in order to obtain positive identifications.


Subject(s)
DNA Fingerprinting , Transients and Migrants , DNA/genetics , DNA Fingerprinting/methods , Humans , Microsatellite Repeats , Seawater
6.
Leg Med (Tokyo) ; 55: 102027, 2022 Mar.
Article in English | MEDLINE | ID: mdl-35121352

ABSTRACT

The lingula is a small bony projection emerging from the medial ridge of the mandibular foramen, subjected to morphological variations. To date, scientific literature has described four different shapes (truncated, triangular, nodular and assimilated) and the relative distributions in different human populations. However, no data are available on Europeans so far. To this purpose, the present study aims to evaluate the distribution of the lingula shapes in the Italian population and to verify its relevance in ancestry estimation. Lingula was analysed in 235 dry mandibles selected among contemporary Italian cemeterial skeletons. Since only well-preserved sides were considered, 453 sides were evaluated according to a classification method, which includes the description of a fifth shape (the bridge shape) and the presence of mixed morphologies. In our sample, the most prevalent shape was the truncated shape (38.6%), followed by the nodular (26.3%), mixed morphologies (15.2%), triangular (10.8%), bridge (5.1%) and assimilated (4.0%) shapes. Within mixed morphologies, the most prevalent were the nodular/truncated (31.9%), nodular/triangular (30.4%), and nodular/assimilated (23.2%). Differently to previous studies, the lingula morphology could not actually offer a concrete and reliable help to ancestry estimation. However, its shape and extension would assume a stronger clinical influence for the execution and success of the alveolar nerve block used in dental and maxillofacial surgery procedures.


Subject(s)
Forensic Medicine , Mandible , Humans
7.
Int J Legal Med ; 135(6): 2581-2594, 2021 Nov.
Article in English | MEDLINE | ID: mdl-34401961

ABSTRACT

Bone taphonomy is a widely investigated topic; however, few data are available concerning marine bone taphonomy, especially on remains recovered from great depths and with short post-mortem intervals. To date, few studies have evaluated the bony changes which occur in seawater compared to samples with different post-mortem histories, and none through a comparative analysis of different approaches. To this purpose, this pilot study aims to examine the influence of seawater on bone preservation compared to other depositional contexts by multiple perspectives. Forty-nine human bone samples (femurs or tibiae) recovered from different environments (sea water, fresh water, outdoor, burial in coffin) were compared by macroscopic, microscopic and bone densitometric approaches. In order to investigate organic and inorganic components, undecalcified and decalcified histology of thin sections was performed. The analyses revealed a well-preserved bone tissue both macroscopically (92%) and microscopically (97% and 95% for undecalcified and decalcified sections). No significant differences were detected from radiological densitometric investigations (BMD = 1.6 g/cm2 ± 0.1), except between old and young individuals (p value < 0.001). Differences were observed for body decomposition and few scavenged samples (3/15). However, even if slight variations were observed, no relation was recorded with the depositional contexts. We found a similar bone preservation in the four environments at the time of recovery, both macroscopically and microscopically, but also with radiological densitometric investigations. Our observations enriched the literature on bone taphonomy, providing data on bone tissue preservation in the early post-mortem period from a multidisciplinary perspective, paving the way for further studies on the topic.


Subject(s)
Bone Density , Bone and Bones/physiology , Seawater , Tissue Preservation , Adolescent , Adult , Body Remains/physiology , Burial , Female , Fresh Water , Humans , Italy , Male , Middle Aged , Pilot Projects , Postmortem Changes , Soil , Young Adult
8.
Genes (Basel) ; 12(2)2021 01 22.
Article in English | MEDLINE | ID: mdl-33499220

ABSTRACT

The efficient extraction of DNA from challenging samples, such as bones, is critical for the success of downstream genotyping analysis in molecular genetic disciplines. Even though the ancient DNA community has developed several protocols targeting small DNA fragments that are typically present in decomposed or old specimens, only recently forensic geneticists have started to adopt those protocols. Here, we compare an ancient DNA extraction protocol (Dabney) with a bone extraction method (Loreille) typically used in forensics. Real-time quantitative PCR and forensically representative typing methods including fragment size analysis and sequencing were used to assess protocol performance. We used four bone samples of different age in replicates to study the effects of both extraction methods. Our results confirm Loreille's overall increased gain of DNA when enough tissue is available and Dabney's improved efficiency for retrieving shorter DNA fragments that is beneficial when highly degraded DNA is present. The results suggest that the choice of extraction method needs to be based on available sample, degradation state, and targeted genotyping method. We modified the Dabney protocol by pooling parallel lysates prior to purification to study gain and performance in single tube typing assays and found that up to six parallel lysates lead to an almost linear gain of extracted DNA. These data are promising for further forensic investigations as the adapted Dabney protocol combines increased sensitivity for degraded DNA with necessary total DNA amount for forensic applications.


Subject(s)
Age Determination by Skeleton/methods , Bone and Bones , DNA, Ancient , Forensic Genetics/methods , Age Factors , Bone and Bones/metabolism , DNA, Mitochondrial , High-Throughput Nucleotide Sequencing , Humans , Microsatellite Repeats , Polymorphism, Single Nucleotide , Real-Time Polymerase Chain Reaction , Sequence Analysis, DNA
9.
J Forensic Sci ; 65(6): 2098-2107, 2020 Nov.
Article in English | MEDLINE | ID: mdl-32809248

ABSTRACT

Many studies in the literature have highlighted the utility of virtual 3D databanks as a substitute for real skeletal collections and the important application of radiological records in personal identification. However, none have investigated the accuracy of virtual material compared to skeletal remains in nonmetric variant analysis using 3D models. The present study investigates the accuracy of 20 computed tomography (CT) 3D reconstruction models compared to the real crania, focusing on the quality of the reproduction of the real crania and the possibility to detect 29 dental/cranial morphological variations in 3D images. An interobserver analysis was performed to evaluate trait identification, number, position, and shape. Results demonstrate a false bone loss in 3D models in some cranial regions, specifically the maxillary and occipital bones in 85% and 20% of the samples. Additional analyses revealed several difficulties in the detection of cranial nonmetric traits in 3D models, resulting in incorrect identification in circa 70% of the traits. In particular, pitfalls included the detection of erroneous position, error in presence/absence rates, in number, and in shape. The lowest percentages of correct evaluations were found in traits localized in the lateral side of the cranium and for the infraorbital suture, mastoid foramen, and crenulation. The present study highlights important pitfalls in CT scan when compared with the real crania for nonmetric analysis. This may have crucial consequences in cases where 3D databanks are used as a source of reference population data for nonmetric traits and pathologies and during bone-CT comparisons for identification purposes.


Subject(s)
Computer Simulation , Imaging, Three-Dimensional , Skull/anatomy & histology , Skull/diagnostic imaging , Tomography, X-Ray Computed , Bone Resorption/diagnostic imaging , Bone Resorption/pathology , Forensic Anthropology , Humans , Reproducibility of Results
10.
Electrophoresis ; 41(5-6): 386-393, 2020 03.
Article in English | MEDLINE | ID: mdl-31967656

ABSTRACT

The long-term survival of RNA in postmortem tissues is a tricky topic. Many aged/forensic specimens show, in fact, high rates of null/inconclusive PCR-based results, while reliable outcomes were sometimes achieved from archaeological samples. On the other hand, several data show that the RNA is a molecule that survives even to several physical-chemical stresses. In the present study, a simple protocol, which was already developed for the prolonged hydrolysis of DNA, was applied to a RNA sample extracted from blood. This protocol is based on the heat-mediated (70°C) hydrolysis for up to 36 h using ultrapure water and di-ethyl-pyro-carbonate-water as hydrolysis medium. Measurable levels of depurination were not found even if microfluidic devices showed a progressive pattern of degradation. The reverse transcription/quantitative PCR analysis of two (60 bp long) housekeeping targets (glyceraldehyde-3-phosphate dehydrogenase and porphobilinogen deaminase) showed that the percentage of amplifiable target (%AT) decreased in relation to the duration of the damaging treatment (r2 > 0.973). The comparison of the %AT in the degraded RNA and in the DNA samples that underwent the same damaging treatment showed that the %AT is always higher in RNA, reaching up to three orders of magnitude. Lastly, even the end-point PCR of blood-specific markers gave reliable results, which is in agreement with the body fluid origin of the sample. In conclusion, all the PCR-based results show that RNA maintains the ability to be retro-transcribed in short cDNA fragments even after 36 h of incubation at 70°C in mildly acidic buffers. It is therefore likely that the long-term survival of RNA samples depends mainly on the protection against RNAase attacks rather than on environmental factors (such as humidity and acidity) that are instead of great importance for the stability of DNA. As a final remark, our results suggest that the RNA analysis can be successfully performed even when DNA profiling failed.


Subject(s)
Forensic Genetics , Polymerase Chain Reaction , RNA , DNA, Complementary/analysis , DNA, Complementary/chemistry , DNA, Complementary/genetics , Humans , RNA/analysis , RNA/chemistry , RNA/genetics , RNA Stability , Sensitivity and Specificity
11.
Forensic Sci Int Genet ; 44: 102156, 2020 01.
Article in English | MEDLINE | ID: mdl-31707115

ABSTRACT

On October 3rd, 2013 a boat carrying more than 500 migrants coming mostly from the Horn of Africa (Eritrea, Somalia, Ethiopia) sank near Lampedusa, a small Italian Island in the middle of the Mediterranean Sea. The recovered bodies were examined by a forensic team, and post mortem data (anthropological and odontological records, and DNA) were collected for identification. Genetic profiles based on 16 autosomal STRs were acquired from both victims and putative relatives recruited following an international call. The final genetic database included 363 victims and 43 reference persons from 36 independent families recruited until mid-2017, who were missing 35 first-degree and 6 second-degree relatives. A pairwise blind search approach was used to identify familial relationships within the victims and between victims and putative relatives. Two statistics were calculated, the Identity by State (IBS) and the Identity by Descent (IBD), the latter by using the DVI module of the FAMILIAS3 software to compute LRs and posterior probabilities. The putative identifications were confirmed in pedigree analysis using the information provided by the relatives. In selected cases, additional autosomal and lineage (Y-chromosome and mtDNA) markers were typed. Some critical points were highlighted: the lack for accurate allele and haplotype frequencies in African populations, especially for the lineage markers, and the need for a shared approach to the biostatistical interpretation of the results in DVI. In the end, 29 first-degree (parent-child and full sibs) out of 35 missing (83%), and 3 out of 6 of second-degree relatives (50%) showed a high statistical confidence for a positive identification. This study represents the first attempt to systematically deal with the genetic identification of African migrants who died in the Mediterranean Sea. The methodological and statistical approach used in this study was proved to be reliable and appropriate for future genetic identifications in other similar mass disasters.


Subject(s)
DNA Fingerprinting/methods , Disaster Victims , Forensic Genetics/methods , Pedigree , Accidents , Chromosomes, Human, Y , DNA, Mitochondrial/genetics , Disasters , Gene Frequency , Humans , Microsatellite Repeats , Ships , Transients and Migrants
12.
Data Brief ; 20: 1237-1243, 2018 Oct.
Article in English | MEDLINE | ID: mdl-30238033

ABSTRACT

This work provides a protocol for the in vitro production of damaged DNA samples. In particular, heat-mediated hydrolysis of the samples at 70 °C in ultrapure water was performed in 1.7 mL Eppendorf tubes sealed by Parafilm for 0-36 h. The chemical/physical features of the resulting samples are described. After normalization of the qPCR data, these were compared with those obtained from samples treated for 0-10 h in a previous study.

13.
Forensic Sci Int Genet ; 36: 148-151, 2018 09.
Article in English | MEDLINE | ID: mdl-30025281

ABSTRACT

In 1976 human remains of seven individuals were discovered in a storage pit located within the Late Bronze Age (9th century B.C.) settlement Stillfried an der March, Austria. In contrast to the common funeral rite of cremation typical for the Urnfield culture (1300-800 B.C.) the individuals' skeletal remains were found outstandingly preserved (Figure S1). As a result, the burial was subject to various investigations, including two conflicting genealogical pedigree reconstructions, one of which was favoured by later geological fingerprinting. We performed mitochondrial (mt)DNA testing in order to genetically characterize the remains and shed light into the matrilineal relationship of the seven individuals that were earlier anthropologically identified as three adults (two women and a man) and four subadults (one female and three males). MtDNA was analysed using Primer Extension Capture and Massively Parallel Sequencing. The results were by and large in conflict with both pedigree models but confirmed some of the details that were elaborated in previous studies. Whereas both pedigree models suggested that all children were related to one or both females, mtDNA analyses revealed that only one subadult male resulted in the same mitotype as one adult female. All other children yielded different mitotypes indicating that they were maternally unrelated to the two females and between each other.


Subject(s)
DNA, Mitochondrial/genetics , Pedigree , Austria , Child , Child, Preschool , DNA Fingerprinting , DNA, Mitochondrial/isolation & purification , Female , High-Throughput Nucleotide Sequencing , History, Ancient , Humans , Male , Polymerase Chain Reaction , Sequence Analysis, DNA , Tooth/chemistry
14.
Anal Biochem ; 549: 107-112, 2018 05 15.
Article in English | MEDLINE | ID: mdl-29551671

ABSTRACT

Heat-mediated hydrolysis of DNA is a simple and inexpensive method for producing damaged samples in vitro. Despite heat-mediated DNA hydrolysis is being widely used in forensic and clinical validation procedures, the lack of standardized procedures makes it impossible to compare the intra and inter-laboratory outcomes of the damaging treatments. In this work, a systematic approach to heat induced DNA hydrolysis was performed at 70 °C for 0-18 h to test the role both of the hydrolysis buffer and of the experimental conditions. Specifically, a trial DNA sample, resuspended in three different media (ultrapure water, 0.1% DEPC-water and, respectively, TE) was treated both in Eppendorf tubes ("Protocol P") and in Eppendorf tubes provided with screwcaps ("Protocol S"). The results of these comparative tests were assessed by normalization of the qPCR results. DEPC-water increased the degradation of the samples up to about 100 times when compared to the ultrapure water. Conversely, the TE protected the DNA from degradation whose level was about 1700 times lower than in samples treated in ultrapure water. Even the employment of the "Protocol S" affected the level of degradation, by consistently increasing it (up to about 180 times in DEPC-water). Thus, this comparative approach showed that even seemingly apparently trivial and often underestimated parameters modify the degradation level up to 2-3 orders of magnitude. The chemical-physical reasons of these findings are discussed together with the role of potential factors such as enhanced reactivity of CO2, ROS, NOx and pressure, which are likely to be involved. Since the intra and inter-laboratory comparison of the outcomes of the hydrolytic procedure is the first step toward its standardization, the normalization of the qPCR data by the UV/qPCR ratio seems to be the simplest and most reliable way to allow this. Finally, the supplying (provided with the commercial qPCR kits) of a DNA sample whose degree of degradation is well documented could be helpful in ISO/IEC 17025 validation procedures and in proficiency testing.


Subject(s)
DNA Damage , DNA/chemistry , DNA/isolation & purification , Real-Time Polymerase Chain Reaction/standards , Adult , Humans , Hydrolysis , Male , Real-Time Polymerase Chain Reaction/methods , Reference Standards
15.
Forensic Sci Int ; 285: 121-128, 2018 Apr.
Article in English | MEDLINE | ID: mdl-29482110

ABSTRACT

Every year thousands of migrants die during the endeavour to reach the Italian coasts, making the Mediterranean the theatre of one of the greatest tragedies of mankind. Over 60% of these victims is buried unidentified: one of the reasons behind this is related to the specific difficulties and lack of strategies concerning AM and PM data collection. The present article describes how Italy is trying to face the problem of migrant identification, thanks to the collaboration between government, the Italian national police and universities. In particular, this is the first pilot study carried out to identify the victims of the second greatest tragedy of its kind off the Italian coast, near Lampedusa, on October 3rd 2013, which caused 366 victims. The present article shows the strategies conceived to collect postmortem and especially antemortem data and to compare them to identify matches, using medicolegal, anthropological, odontological and genetic approaches. Thirty-one victims out of 53 missing sought by relatives were identified (58.5%). The type and the quality of antemortem data available, generally photos and videos, pinpoints the importance of the face and the body for identification when the bodies are well preserved and how DNA analyses may at times present difficulties. In fact, critical points emerged concerning especially the lack of genetic information of the populations to which the victims belonged, the number of genetic markers needed to reach a statistical support for the identification and the need to adopt lineage markers such as mitochondrial DNA and Y-chromosome polymorphisms to identify parental relationships. This pilot study however has proven that families continue to seek their relatives and that it is possible, as well as mandatory, to identify migrant victims in spite of the difficulties in the collection of antemortem and postmortem data. In addition, considering the peculiar scenario, novel strategies for positive identification have to be defined in each field (anthropological, odontological and genetic) as well as in combination.


Subject(s)
Biometric Identification/methods , Body Remains , DNA Fingerprinting , Forensic Sciences/methods , Transients and Migrants , Accidents , DNA/isolation & purification , Humans , Mediterranean Sea , Microsatellite Repeats , Photography , Pilot Projects , Real-Time Polymerase Chain Reaction , Ships , Tattooing
16.
Electrophoresis ; 38(8): 1163-1174, 2017 04.
Article in English | MEDLINE | ID: mdl-28078776

ABSTRACT

Next generation sequencing (NGS) is the emerging technology in forensic genomics laboratories. It offers higher resolution to address most problems of human identification, greater efficiency and potential ability to interrogate very challenging forensic casework samples. In this study, a trial set of DNA samples was artificially degraded by progressive aqueous hydrolysis, and analyzed together with the corresponding unmodified DNA sample and control sample 2800 M, to test the performance and reliability of the ForenSeqTM DNA Signature Prep kit using the MiSeq Sequencer (Illumina). The results of replicate tests performed on the unmodified sample (1.0 ng) and on scalar dilutions (1.0, 0.5 and 0.1 ng) of the reference sample 2800 M showed the robustness and the reliability of the NGS approach even from sub-optimal amounts of high quality DNA. The degraded samples showed a very limited number of reads/sample, from 2.9-10.2 folds lower than the ones reported for the less concentrated 2800 M DNA dilution (0.1 ng). In addition, it was impossible to assign up to 78.2% of the genotypes in the degraded samples as the software identified the corresponding loci as "low coverage" (< 50x). Amplification artifacts such as allelic imbalances, allele drop outs and a single allele drop in were also scored in the degraded samples. However, the ForenSeqTM DNA Sequencing kit, on the Illumina MiSeq, was able to generate data which led to the correct typing of 5.1-44.8% and 10.9-58.7% of 58 of the STRs and 92 SNPs, respectively. In all trial samples, the SNP markers showed higher chances to be typed correctly compared to the STRs. This NGS approach showed very promising results in terms of ability to recover genetic information from heavily degraded DNA samples for which the conventional PCR/CE approach gave no results. The frequency of genetic mistyping was very low, reaching the value of 1.4% for only one of the degraded samples. However, these results suggest that further validation studies and a definition of interpretation criteria for NGS data are needed before implementation of this technique in forensic genetics.


Subject(s)
DNA Fingerprinting/methods , Forensic Genetics/methods , Reagent Kits, Diagnostic/standards , Sequence Analysis, DNA/methods , DNA Fingerprinting/standards , Electrophoresis, Capillary , Forensic Genetics/standards , Genotype , Humans , Hydrolysis , Reproducibility of Results , Sequence Analysis, DNA/standards
17.
Am J Phys Anthropol ; 158(4): 636-45, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26265488

ABSTRACT

OBJECTIVES: The variation and persistence of blood components, in particular red blood cells (RBCs), within bone tissue during the decomposition process, especially at the early stages and in different taphonomic conditions, has never been thoroughly investigated, regardless of the fact that knowing how blood survives or degrades within bone could be of help in solving many anthropological issues, such as trauma analysis and interpretation. MATERIALS AND METHODS: This research investigated the influence of time and taphonomy on the persistence and detectability of blood components in parietal bone fragments (of different post mortem periods and taphonomic conditions) through histological (Hematoxilin and Eosin, HE) and immunohistochemical (Glycophorin A, GYPA) analyses. RESULTS: The immunohistochemical investigation for GYPA showed the presence of RBCs under the form of erythrocyte debris or residues otherwise morphologically unidentifiable using only HE staining. Hence, while well-defined RBCs can be observed only in the first week of decomposition, afterward these structures can be detectable with certainty only by immunohistochemical analysis, which reveals discrete quantities of RBC residues also in dry bone (post mortem interval, or PMI, of 15 years), but not in archaeological samples, in which the greater PMI and the different taphonomic conditions together could be the answer behind such difference. DISCUSSION: This study highlights the usefulness and potential of immunohistochemical detection of GYPA in RBC investigation and gives a realistic idea of the persistence and detectability of erythrocytes in different osteological taphonomic conditions, in contrast to results reported by some authors in literature. Another important result concerns the detection of RBC residues in dry bone, which opens the way to the possible use of RBCs in trauma interpretation.


Subject(s)
Bone and Bones/chemistry , Erythrocytes/chemistry , Forensic Anthropology , Fossils , Death , Glycophorins , Humans
SELECTION OF CITATIONS
SEARCH DETAIL
...