Showing papers in "International Journal of Legal Medicine in 2006"

Age estimation in children by measurement of open apices in teeth.

Abstract: This paper concerns a method for estimating the age of children based on their teeth. The sample consisted of 455 Italian white children (213 boys, 242 girls) aged between 5 and 15 years. The purpose of the present investigation was to present a method for assessing chronological age based on the relationship between age and measurement of the open apices in teeth. Pearson's correlation coefficients between age and these variables showed that the correlations between age and the open apices in teeth were significant and negative. Furthermore, gender and the number of teeth with the apical end of the root canals completely closed (N(0)) showed a significant correlation with chronological age. With the aid of a stepwise multiple regression model, a linear relationship between open apices, N(0), and age was shown. Statistical analysis indicated that these morphological variables explain 83.6% of the variations in estimated chronological age. The median of residual errors between the actual and estimated ages was -0.035 years [interquartile range (IQR)=1.18 years].

The impact of economic progress and modernization in medicine on the ossification of hand and wrist.

Abstract: One of the main criteria used for age estimations of young living subjects is the developmental status of the ossification of hand bones. The impact of economic progress and modernization in medicine on ossification rates in a given population still requires further clarification. We selected 36 samples from literature for which the ossification status had been determined with the Greulich–Pyle method and analyzed specific economic data (per capita income) and demographic data (life expectancy at birth) as parameters of modernization. To describe the influence of these parameters on the rate of ossification, we performed a regression analysis and found that a relatively high level of economic progress and modernization in medicine coincides with high ossification rates, while relatively low modernization seems to delay ossification. When performing age estimations, the expert opinion should therefore pay attention to the issue of different modernization levels.

Sudden cardiac death during anabolic steroid abuse: morphologic and toxicologic findings in two fatal cases of bodybuilders.

Abstract: We report two cases of sudden cardiac death (SCD) involving previously healthy bodybuilders who were chronic androgenic–anabolic steroids users. In both instances, autopsies, histology of the organs, and toxicologic screening were performed. Our findings support an emerging consensus that the effects of vigorous weight training, combined with anabolic steroid use and increased androgen sensitivity, may predispose these young men to myocardial injury and even SCD.

Encyclopedia of Forensic and Legal Medicine

Abstract: The Encyclopedia of Forensic and Legal Medicine is a four-volume set covering a wide range of disciplines and specialities in the field of forensic and legal medicine. It contains more than 290 articles written by internationally renowned professionals. The topics are arranged in an alphabetical order, and the key fields are clearly laid out. The chapters are fully up-todate, and the contents are presented in a textbook manner. Each chapter provides information enabling specific “Further reading” as well as useful links to related topics. Several chapters deal with topics highly relevant to the current situation such as “Accreditation”, “Computer crime and digital evidence”, “Internet”, “Ritualistic crime”, “Terrorism” and “Torture”. The encyclopedia contains extremely useful details regarding practical forensic casework. For instance, the chapter “Children” describes the various stages of development and growth of children in great depth as well as topics such as emotional, physical and sexual abuse of children, causes of sudden natural infant and childhood death and non-inflicted causes of death. Furthermore, the encyclopedia gives a representative overview about medical malpractice in different medical fields, which is helpful for the writing of expert witness reports. The encyclopedia effectively links different but related specialities such as forensic toxicology, forensic psychology and psychiatry, forensic anthropology, forensic botany and forensic science. It connects forensic medical and the corresponding legal aspects. The text is accompanied by high-quality, full-colour and well-explained images, illustrations, diagrams and tables. The encyclopedia can be recommended as the major reference source for forensic and legal medicine not only to forensic pathologists but also to medical practitioners, scientists, students, judges and lawyers.

Population differences of two coding SNPs in pigmentation-related genes SLC24A5 and SLC45A2.

Abstract: The two genes SLC24A5 and SLC45A2 were recently identified as major determinants of pigmentation in humans and in other vertebrates. The allele p.A111T in the former gene and the allele p.L374F in the latter gene are both nearly fixed in light-skinned Europeans, and can therefore be considered ancestry informative marker (AIMs). AIMs are becoming useful for forensic identification of the phenotype from a DNA profile sampled, for example, from a crime scene. Here, we generate new allelic data for these two genes from samples of Chinese, Uygurs, Ghanaians, South African Xhosa, South African Europeans, and Sri Lankans (Tamils and Sinhalese). Our data confirm the earlier results and furthermore demonstrate that the SLC45A2 allele is a more specific AIM than the SLC24A5 allele because the former clearly distinguishes the Sri Lankans from the Europeans.

Postmortem imaging of blood and its characteristics using MSCT and MRI

Abstract: The rapid development of computed tomography (CT) and magnetic resonance imaging (MRI) led to the introduction and establishment in postmortem investigations. The objectives of this preliminary study were to describe the imaging appearances of the early postmortem changes of blood after cessation of the circulation, such as sedimentation, postmortem clotting, and internal livores, and to give a few first suggestions on how to differentiate them from other forensic findings. In the Virtopsy project, 95 human corpses underwent postmortem imaging by CT and MRI prior to traditional autopsy and therefore 44 cases have been investigated in this study. Postmortem alterations as well as the forensic relevant findings of the blood, such as internal or subcutaneous bleedings, are presented on the basis of their imaging appearances in multislice CT and MRI.

A new “miniSTR-multiplex” displaying reduced amplicon lengths for the analysis of degraded DNA

Abstract: A multiplex PCR was designed for the loci D2S1338, D16S539, D18S51, TH01 and FGA using redesigned primers in order to reduce the lengths of the amplification products compared to the designs used in commercially available multiplex PCR kits, also including amelogenin. The new PCR primers were used to amplify highly degraded DNA from casework samples, which had shown no or only poor results for these loci in previous analyses with standard primer sets. The application of the new miniSTR-multiplex resulted in an increased overall typing success rate for degraded DNA samples. In a concordance study between the conventional and the newly designed primers, no genotype differences were revealed in 124 randomly selected individuals.

The influence of slice thickness on assessment of clavicle ossification in forensic age diagnostics

Abstract: Computed tomography scans originally obtained to assess the ossification status of the medial clavicular epiphyses of 40 live subjects for forensic age estimation purposes were analysed. From the data acquired we reconstructed images with slice thicknesses of 1, 3, 5 and 7 mm, and based on the classification of stages by Schmeling et al. (Int J Legal Med 118:5–8, 2004), we determined the ossification stage for each reconstructed slice thickness, separately for both sides. Of the 80 clavicular epiphysial plates examined, seven displayed slice-thickness-dependent differences at certain ossification stages. In one case a slice thickness of 1 mm led to a different diagnosis of the ossification stage than a slice thickness of 3 mm, in three cases the diagnoses differed between the slice thicknesses of 3 and of 5 mm, and in another three cases, between 5 and 7 mm. We therefore conclude that for age estimation purposes, the slice thickness should be 1 mm to ensure maximum accuracy and diagnostic reliability.

DNA Commission of the International Society of Forensic Genetics (ISFG): An update of the recommendations on the use of Y-STRs in forensic analysis

Abstract: The DNA Commission of the International Society of Forensic Genetics (ISFG) regularly publishes guidelines and recommendations concerning the application of DNA polymorphisms to the problems of human identification. A previous recommendation published in 2001 has already addressed Y-chromosome polymorphisms, with particular emphasis on short tandem repeats (STRs). Since then, the use of Y-STRs has become very popular, and numerous new loci have been introduced. The current recommendations address important aspects to clarify problems regarding the nomenclature, the definition of loci and alleles, population genetics and reporting methods.

Carpals and epiphyses of radius and ulna as age indicators

Abstract: Estimation of skeletal age using radiographic images is widely used for assessing biological growth in clinical and auxological studies. The most frequent areas used for age estimation in children and adolescents are tooth and wrist/hand, both giving good results with only a low level of radiation. In particular, ossification of the carpals shows good agreement with chronological age. This study of a sample of 150 Italian children and adolescents aged between 5 and 17 years focused on analyzing the possible applications of the proportion of carpal area (Ca) mineralization as a criterion of age estimation. The ratio between the total area of carpal bones and epiphyses of the ulna and radius (Bo) and Ca was calculated. This ratio (Bo/Ca) was used for linear regression analysis. The regression model, describing age as a linear function of the ratio Bo/Ca, yielded the following equation: Age=−3.253+0.719 g+20.610 Bo/Ca, and explained 83% of the total variance (R2=0.83). The median of the absolute values of residuals (observed age minus predicted age) was 0.08 years, with a quartile deviation of 1.59 years, and a standard error of estimate of 1.19 years.

Finite element modelling of human head injuries caused by a fall.

Abstract: Finite element models (FEMs) can be used as prediction tools for human head injuries caused by falls. The purpose of this paper is to demonstrate the relevance of using human head FEM to assess the possible mechanism for the origin of head injuries. The FEM of the human head used in this study was developed in the late 1990s at the University Louis Pasteur of Strasbourg (ULP) and has been validated for human head impacts for simulating human head injuries caused by car accidents. Its use in legal medicine appears to be very useful for comparing different injury mechanisms. We present the simulation obtained for two witnessed falls of the same individual, and compare our results to tolerance limits of the main human head injuries. We show that this tool can be used to discuss the possible mechanism of injury encountered for the observed lesions in a forensic case. It can also help to distinguish between possible and impossible human head injury mechanisms.

DXS10079, DXS10074 and DXS10075 are STRs located within a 280-kb region of Xq12 and provide stable haplotypes useful for complex kinship cases

Abstract: The evaluation of the short tandem repeat (STR) markers DXS10079, DXS10074 and DXS10075 was amended to establish a STR cluster spanning a genetic distance<1 cM. These three STRs are located within a 280-kb region at Xq12 and provide stable haplotypes useful for solving complex kinship cases. Theoretically, this cluster could give rise to 2,548 different haplotypes in the German population and the genotyping of 781 men revealed the presence of 172 haplotypes. Since the three STRs were shown to be in strong linkage disequilibrium (LD), haplotype frequencies cannot be computed on the basis of a single locus allele frequency alone but have to be estimated directly. Here, we present data on linkage, haplotype frequencies and LD in a German population. Further clusters from other regions of the X chromosome will be published in the future to cover the chromosome with a well-structured network of highly informative sites.

A new Web site compiling forensic chromosome X research is now online.

Abstract: We would like to announce the opening of a new Web site (http://www.chrx-str.org), which contains a database surveying current research on chromosome X markers used for forensic purposes, evolutionary anthropology and other genetic research. Currently, we summarise short tandem repeat data with regard to the physical and genetic localisation, repeat structure, allele nomenclature, mutation rates and population genetics. In the future, we may include diallelic markers. The results contained in this database come from published journal articles. The authors of published articles are invited to complement their own papers by submitting data obtained from follow-up studies here. Furthermore, population data which are not able to find space in journals may be published at this Web site. The growing field of ChrX haplotyping is producing an extensive amount of data, which requires a place that can complement journal publications.

3-D imaging and quantitative comparison of human dentitions and simulated bite marks.

Abstract: This study presents a technique developed for 3-D imaging and quantitative comparison of human dentitions and simulated bite marks. A sample of 42 study models and the corresponding bites, made by the same subjects in acrylic dental wax, were digitised by laser scanning. This technique allows image comparison of a 3-D dentition with a 3-D bite mark, eliminating distortion due to perspective as experienced in conventional photography. Cartesian co-ordinates of a series of landmarks were used to describe the dentitions and bite marks, and a matrix was created to compare all possible combinations of matches and non-matches using cross-validation techniques. An algorithm, which estimated the probability of a dentition matching its corresponding bite mark, was developed. A receiver operating characteristic graph illustrated the relationship between values for specificity and sensitivity. This graph also showed for this sample that 15% of non-matches could not be distinguished from the true match, translating to a 15% probability of falsely convicting an innocent person.

Stability of ethyl glucuronide in urine, post-mortem tissue and blood samples

Abstract: The stability of ethyl glucuronide (EtG) under conditions of degradation was examined in urine samples of nine volunteers and in post-mortem tissue (liver, skeletal muscle) and blood taken from seven corpses at autopsies. Analysis was performed via LC-MS/MS. EtG concentrations in urine samples ranged from 2.5 to 296.5 mg/l. When stored at 4°C in airtight test tubes, EtG concentrations remained relatively constant; when stored at room temperature (RT) for 5 weeks in ventilated vials, variations of EtG concentrations ranged from a 30% decrease to an 80% increase, with an average of 37.5% increase. Liver and skeletal muscle tissue of three corpses with positive blood alcohol concentrations (BAC; ranging from 0.106 to 0.183 g%) were stored for 4 weeks and analysed periodically. EtG concentrations decreased 27.7% on average in 4 weeks storage at RT but EtG was still detectable in all samples with initial EtG concentrations higher than 1 μg/g. Blood and liver samples of four corpses with negative BACs were stored at RT after addition of 0.1 g% ethanol, and no new formation of EtG was observed.

Validation of a DNA-based method for identifying Chrysomyinae (Diptera: Calliphoridae) used in a death investigation.

Abstract: Many authors have proposed DNA-based methods for identifying an insect specimen associated with human remains. However, almost no attempt has been made to validate these methods using additional observations. We tested a protocol for identifying insects in the blow fly subfamily Chrysomyinae (Diptera: Calliphoridae) often found to be associated with a human corpse in Canada or the USA. This method uses phylogenetic analysis of DNA sequence from a short segment of the mitochondrial gene for cytochrome oxidase one (COI). Test chrysomyine COI sequences were obtained from 245 newly sequenced specimens and 51 specimens from the published literature. Published sequences from representatives of nonchrysomyine genera were also included to check for the possibility of a false positive identification. All of the chrysomyine test haplotypes were correctly identified with strong statistical support, and there were no false positives. This method appears to be an accurate and robust technique for identifying chrysomyine species from a death investigation in this geographic region. The far northern species Protophormia atriceps was not evaluated; therefore, caution is required in applying this method at very high latitudes in North America.

Does imaging technology overcome problems of conventional postmortem examination? A trial of computed tomography imaging for postmortem examination.

Abstract: We used a mobile computed tomography (CT) unit for postmortem examinations of deceased subjects to see how many mistakes on cause-of-death diagnoses were made in Japan. In 5 of 20 cases, the cause of death determined by CT was different from the diagnosis made by superficial postmortem examination. In one case, the superficial examination suggested no trauma, whereas a subdural hematoma was found on cranial CT images. We concluded that postmortem examinations in Japan were not effective when screening for crimes or accidents. Using a mobile CT scanner in postmortem examination may be a viable method of screening for causes of deaths, although it cannot be used as a substitute for autopsy.

Mitochondrial DNA control region sequences in Koreans: identification of useful variable sites and phylogenetic analysis for mtDNA data quality control

Abstract: We have established a high-quality mtDNA control region sequence database for Koreans. To identify polymorphic sites and to determine their frequencies and haplotype frequencies, the complete mtDNA control region was sequenced in 593 Koreans, and major length variants of poly-cytosine tracts in HV2 and HV3 were determined in length heteroplasmic individuals by PCR analysis using fluorescence-labeled primers. Sequence comparison showed that 494 haplotypes defined by 285 variable sites were found when the major poly-cytosine tract genotypes were considered in distinguishing haplotypes, whereas 441 haplotypes were found when the poly-cytosine tracts were ignored. Statistical parameters indicated that analysis of partial mtDNA control region which encompasses the extended regions of HV1 and HV2, CA dinucleotide repeats in HV3 and nucleotide position 16497, 16519, 456, 489 and 499 (HV1ex+HV2ex+HV3CA+5SNPs) and the analysis of another partial mtDNA control region including extended regions of HV1 and HV2, HV3 region and nucleotide position 16497 and 16519 (HV1ex+HV2ex+HV3+2SNPs) can be used as efficient alternatives for the analysis of the entire mtDNA control region in Koreans. Also, we collated the basic informative SNPs, suggested the important mutation motifs for the assignment of East Asian haplogroups, and classified 592 Korean mtDNAs (99.8%) into various East Asian haplogroups or sub-haplogroups. Haplogroup-directed database comparisons confirmed the absence of any major systematic errors in our data, e.g., a mix-up of site designations, base shifts or mistypings.

Maximum intensity projection of cranial computed tomography data for dental identification.

Abstract: Dental radiographs play the major role in the identification of victims in mass casualties besides DNA. Under circumstances such as those caused by the recent tsunami in Asia, it is nearly impossible to document the entire dentition using conventional x-rays as it would be too time consuming. Multislice computed tomography can be used to scan the dentition of a deceased within minutes, and the postprocessing software allows visualization of the data adapted to every possible antemortem x-ray for identification. We introduce the maximum intensity projection of cranial computed tomography data for the purpose of dental identification exemplarily in a case of a burned corpse. As transportable CT scanners already exist, these could be used to support the disaster victim identification teams in the field.

MiniX-STR multiplex system population study in Japan and application to degraded DNA analysis

Abstract: We sought to evaluate a more effective system for analyzing X-chromosomal short tandem repeats (X-STRs) in highly degraded DNA. To generate smaller amplicon lengths, we designed new polymerase chain reaction (PCR) primers for DXS7423, DXS6789, DXS101, GATA31E08, DXS8378, DXS7133, DXS7424, and GATA165B12 at X-linked short tandem repeat (STR) loci, devising two miniX-multiplex PCR systems. Among 333 Japanese individuals, these X-linked loci were detected in amplification products ranging in length from 76 to 169 bp, and statistical analyses of the eight loci indicated a high usefulness for the Japanese forensic practice. Results of tests on highly degraded DNA indicated the miniX-STR multiplex strategies to be an effective system for analyzing degraded DNA. We conclude that analysis by the current miniX-STR multiplex systems offers high effectiveness for personal identification from degraded DNA samples.

Y-chromosomal STR haplotypes in a Northeast Italian population sample using 17plex loci PCR assay

Abstract: One hundred fifty-five unrelated, autochthonous healthy males from Northeast Italy were typed for the 17 Y-chromosome short tandem repeat (STR) (Y-STR) loci DYS456, DYS389I, DYS390, DYS389II, DYS458, DYS19, DYS385, DYS393, DYS391, DYS439, DYS635, DYS392, Y GATA H4, DYS437, DYS438, DYS448 using the AmpFLSTR Yfiler polymerase chain reaction amplification kit. A total of 153 different haplotypes were observed, and among these, 151 were unique, while 2 were found two times. The overall haplotype diversity was 0.9997. Furthermore, 50 father–son pairs, previously confirmed by autosomal STR analysis, were typed using the same set of 17 Y-STR loci, and, among 850 allele transfers, three mutation events were identified, giving an average mutation rate of 3.53×10−3 per locus per generation (95% confidence interval 0.73–1.03).

Cardiac pathology in death from electrocution

Abstract: To better characterize the morphologic changes in electrocution, morphologic changes in the hearts of 21 subjects, who died instantaneously of electrocution, were compared to the hearts of decedents with different types of death. Sixteen myocardial samples per heart were processed for histological examination, and sections were prepared with a variety of specific stains. The frequency, location and extent of myocellular segmentation (stretching and/or rupture) of intercalated discs and associated changes of myocardial bundles and single myocells [myofibre break-up (MFB)] were recorded, quantitatively analysed and statistically evaluated. The frequency of MFB was maximal in cases of electrocution (90%). The findings show that MFB is an ante-mortem change and may be a distinct finding in electrocution.

Postmortem pericardial natriuretic peptides as markers of cardiac function in medico-legal autopsies

Abstract: Atrial natriuretic peptide (ANP) and brain natriuretic peptide (BNP) in the blood are clinical markers for the diagnosis of cardiac failure. This study was a comprehensive analysis of the postmortem pericardial levels of the natriuretic peptides in serial medico-legal autopsy cases (n=263, within 72 h postmortem) to assess their validity in investigating cardiac function. There was no significant relationship of pericardial ANP or BNP levels with postmortem time or the age of the subjects. The ANP and BNP levels showed negative correlations with the pericardial cardiac troponin T level. The ANP level was significantly elevated in drowning cases. Pericardial BNP and the BNP/ANP ratio were significantly higher for chronic congestive heart disease. However, asphyxiation, sharp instrument injury, hyperthermia, and fatal MA poisoning cases showed lower levels for both markers. These observations suggest that elevations in the postmortem pericardial ANP and BNP may mainly depend on acute atrial overload and subacute or chronic cardiac failure, respectively, and may be reduced by advanced myocardial damage.

Experiences in tsunami victim identification.

Abstract: Sir, On 26 December 2004, giant tsunami waves devastated the coast lines of 12 south-east Asian countries, with the number of persons confirmed dead or still missing exceeding 300,000 as of 30 June 2005. Directly after the tsunami had struck Thailand’s holiday resorts on the southwestern coast, tens of thousands of locals and Western holidaymakers were missing, and hourly, more and more were confirmed dead by local authorities via the national and international media. As members of the German Federal Police’s disaster victim identification (DVI), these authors arrived on the island of Phuket, Thailand, on 28 and 30 December 2004, and worked in the region of Phuket and Khao Lak until returning to Germany on 14 January 2005. During the first 2 days after the tsunami had struck, hurried disposal of corpses by cremation or mass burials was performed in the region of Phuket and Khao Lak at some places under the surveillance of local authorities, resulting in bodies being either wrongly or not identified. Thai (local) tsunami victims had been visually “identified” by relatives and friends and were hastily cremated at Wat Yan Yao, at least until 29 December 2004; in addition, mass burials of corpses of believed Thai citizens (as determined by their black hair color, in contrast to those with blonde hair who were believed to be foreigners) were conducted during the first 2 weeks of January 2005 near the city of Phang Nga, not far from the region of Khao Lak (Fig. 1). Under the leadership of the Thai police, the German DVI team worked at three different provisional mortuaries during the early phase of the tsunami operation, handling approximately 400 bodies during the first 3 weeks after the tsunami. Over the first days, identification procedures had to be performed in the open, at a site not far from Phuket airport, since no provisional mortuaries were installed in the region at that time. Most of the deceased that underwent identification procedures at this work site were tsunami victims who had died in Phuket hospital shortly after the disaster had occurred. Since the Thai medical system was not prepared to give those who survived the tsunami immediate and appropriate medical care directly after the disaster—as the medical supply system of any country confronted with a disaster of such vast dimensions would be overstretched—at least hundreds of tsunami victims who initially survived died during the first days after the disaster from respiratory tract infections as a sequel of near-drowning, blunt force trauma or sepsis originating from wound infections. M. Tsokos (*) Institute of Legal Medicine, Department of Forensic Pathology, University of Hamburg, Butenfeld 34, 22529 Hamburg, Germany e-mail: mtsokos@web.de Tel.: +49-40-428032748 Fax: +49-40-428033934

Sudden infant death syndrome and long QT syndrome: an epidemiological and genetic study

Abstract: Sudden infant death syndrome (SIDS) is a frequent cause of death among infants. The etiology of SIDS is unknown and several theories, including fatal ventricular arrhythmias, have been suggested. We performed an epidemiological and genetic investigation of SIDS victims to estimate the presence of inherited long QT syndrome (LQTS) as a contributor for SIDS. Forty-one consecutively collected and unrelated SIDS cases were characterized by clinical and epidemiological criteria. We performed a comprehensive gene mutation screening with single-strand conformation polymorphism analysis and sequencing techniques of the most relevant LQTS genes to assess mutation frequencies. In vitro characterization of identified mutants was subsequently performed by heterologous expression experiments in Chinese hamster ovary cells and in Xenopus laevis oocytes. A positive family history for LQTS was suspected by mild prolonged Q-T interval in family members in 2 of the 41 SIDS cases (5%). In neither case, a family history of sudden cardiac death was present nor a mutation could be identified after thorough investigation. In another SIDS case, a heterozygous missense mutation (H105L) was identified in the N-terminal region of the KCNQ1 (LQTS 1) gene. Despite absence of this mutation in the general population and a high conservational degree of the residue H105 during evolution, electrophysiological investigations failed to show a significant difference between wild-type and KCNQ1(H105L)/minK-mediated I(Ks) currents. Our data suggest that a molecular diagnosis of SIDS related to LQTS genes is rare and that, even when an ion channel mutation is identified, this should be regarded with caution unless a pathophysiological relationship between SIDS and the electrophysiological characterization of the mutated ion channel has been demonstrated.

Reference data for the Thiemann–Nitz method of assessing skeletal age for the purpose of forensic age estimation

Abstract: The aim of this study was to determine the statistical parameters of deviation in the Thiemann–Nitz method for use in forensic age diagnostics. To this effect, 402 hand radiograms, originally taken in two large German cities between 1983 and 2002 for the purpose of diagnosing trauma, were analyzed. At the time of examination, the patients were aged between 10 and 18 years. The study presents the mean, standard deviation, and median, with lower and upper quartiles, for the skeletal ages of 11.0 through 18.0 years. The simple standard deviations range between 0.2 and 1.2 years. To increase the accuracy of age estimates and improve the identification of age-relevant developmental disorders in forensic age estimation practice, the methods for determining skeletal age should always be combined with a physical and dental examination. In addition, the expert opinion should pay attention to the issue of different modernization levels in relevant populations.

Sudden death after isobutane sniffing: a report of two forensic cases

Abstract: The intentional inhalation of a volatile substance (“sniffing”) causing euphoria and hallucinations is an under-recognised form of substance abuse in children and adolescents with a high morbidity and mortality. Sudden death can be caused by cardiac arrhythmia, asphyxia or trauma. Two fatal cases of isobutane sniffing of cigarette lighter refill containing isobutane are reported. Toxicological investigations revealed the presence of isobutane in the heart blood and brain tissue of both cases (case 1: heart blood 0.1 μg/g, brain tissue 2.3 μg/g; case 2: heart blood 4.6 μg/g, brain tissue 17.4 μg/g) and the presence of its metabolite 2-methyl-2-propanol in the heart blood of both cases (0.5 and 1.8 μg/g, respectively). The histological investigations of the inner organs showed similar results in both victims. Autopsy findings, results of the histological and immunohistochemical investigations, toxicological findings and analytical procedures are discussed.

Development of two multiplex PCR systems for the analysis of 12 X-chromosomal STR loci in a northwestern Italian population sample

Abstract: Two multiplex polymerase chain reaction systems for the automated profiling of 12 X-chromosomal short tandem repeat (STR) markers were developed. Multiplex A consisted of DXS6789, DXS6809, GATA172D05, DXS101, DXS8378, and DXS8377. Multiplex B consisted of DXS7132, DXS6800, DXS6801, DXS7424, HPRTB, and DXS10011. The set of amplified X-STRs was designed to include groups of closely linked markers (DXS101–DXS7424 and DXS6789–DXS6801–DXS6809) to generate highly informative haplotypes for kinship testing. A population genetics study of the 12 X-STRs was conducted in a northwestern Italian population sample (n=160, 80 women and 80 men). A diallelic pattern at locus DXS6789 was observed in one man.

Sex-specific fluorescent labelling of cells for laser microdissection and DNA profiling.

Abstract: Sex-specific isolation of cells from mixtures would greatly facilitate forensic casework. Thus, male and female cell mixtures were marked with a fluorescent X/Y-probe CEP X SpectrumOrange/Y SpectrumGreen DNA probe kit for fluorescence in situ hybridization, and single cells were isolated via laser microdissection (LMD). DNA profiling of LMD isolated, hybridized cells showed usable short tandem repeat profiles for at least 20 cells, which are comparable with results from other studies. To simulate casework samples, the method was also optimized for air-dried samples.

Effective strategies for forensic analysis in the mitochondrial DNA coding region.

Abstract: Recently, it has been recognized that accessing information in the mtDNA coding region can provide additional forensic discrimination with respect to the standard typing of the D-loop region, augmenting the sometimes rather limited forensic power of mtDNA testing. Here, we discuss considerations relating to maximally effective approaches for recovering additional discrimination in the coding region, bearing in mind that (1) DNA quality and quantity in typical mtDNA casework usually restrict the amount of additional sequence that can be obtained, and (2) the need for additional discrimination primarily arises when common HV1/HV2 types are encountered. Most investigators have sought additional discrimination by sequencing short segments of coding region that are thought to be particularly variable. Unfortunately, efforts in this regard have generally failed to appreciate that most variation in the coding region is redundant with information already present in HV1/HV2 and have therefore overvalued the potential of this approach for providing additional discrimination. An alternative single nucleotide polymorphism-based approach [Int J Legal Med 118:137–146, 2004] has been to identify specific bases that provide resolution in specific common HV1/HV2 types (and related sequences). We investigate several highly relevant data sets wherein the latter approach performs appreciably better than sequencing selected short portions of the coding region. This is true even when only synonymous variation is targeted to minimize the potential for problems arising from discovery of mutations that have reportedly been related to disease.