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To date, there is no systematic investigation of the association of short tandem repeat (STR) typing success rate in soft tissues with different signs of putrefaction. Herein, putrefaction was rated using a newly developed 19-parameter system in soft tissues from a collective of 68 decaying bodies, and DNA yield was determined in 408 samples. DNA integrity was rated using a self-devised pentaplex PCR generating an "integrity score" (Si). STR typing success rate was then assessed for selected cases. DNA yield and Si differed significantly between tissues with kidney on average exhibiting the highest Si values. Statistical analysis revealed that nine parameters were significantly and positively correlated with Si . The observed values for each of these nine parameters were summed up to generate a putrefaction score (Sp) for each sample. Our results show that STR typing success rate can be predicted based on Sp before expensive multiplex STR profiling is performed., (© 2015 American Academy of Forensic Sciences.)

Backspatter from wounds caused by contact shots against a biological target had before been shown to be propelled into firearms' barrels where they can persist and be retrieved from as relevant forensic evidence. Herein, that insight was applied to the investigation of a case of multiple familial homicide with a firearm. Samples of backspatter were collected from the firearm using DNA-free swabs. DNA was extracted from the swabs, and 16 STR systems were PCR-amplified to generate DNA profiles of all victims shot by the firearm. The quality of the resulting DNA profiles was sufficient to exclude the perpetrator as donor and to differentiate the three closely related victims thereby proving that all three victims had been shot by the same firearm from very close or contact distance. A key insight gained from this case was that not only a firearms' barrel inside but other inner surfaces may be charged with profilable DNA., (© 2014 American Academy of Forensic Sciences.)

This article presents a case of suicide by intoxication with various pharmaceuticals, particularly anticonvulsants, combined with the fungicide captan. A cause of death could not be ascertained at autopsy. However, systematic toxicological analysis (STA) including a screening via solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) for (semi) volatile organic compounds revealed results suggesting a possible cause of death. The effects of captan on the human organism, its metabolism, and distribution will be discussed. Macroscopically, the cause of death was unascertained. STA revealed clonazepam, citalopram, and its metabolites, lamotrigine, levetiracetam, lacosamide, clonazepam, captan, and its metabolite tetrahydrophthalimide (THPI). For the first time, it was detected in human viscera. A quantification of THPI was performed to obtain distribution in the organs. The significance of a complete STA must be emphasized. The presence of THPI would have been missed without previous detection of captan. Consequently, this fatality would not have been investigated satisfactorily., (© 2013 American Academy of Forensic Sciences.)

Scientific opinions differ whether the use of stimulants causes deterioration in driving skills. In 1857 of 8709 cases of driving under the influence of drugs, amphetamine-like drugs (amphetamine, methamphetamine, and methylendioxyamphetamine) were present either alone or together with other licit or illicit drugs. In 338 cases, amphetamines were the only psychoactive substance group in plasma at mean, median, and highest concentrations of 0.18, 0.12, and 1.05 mg/L, respectively. A widespread opinion is that after the consumption of amphetamines, centrally stimulating effects with corresponding consequences on safe driving are expected. In contrast, many cases were observed that rather suggested an influence of centrally sedating substances when considering the psycho-physical conditions. Relations between concentration and effect could not be established. The apparent sedation is probably the consequence of sleep deprivation during an amphetamine binge and the after-effects of the drug., (© 2012 American Academy of Forensic Sciences.)

Micro-RNAs (miRNAs) are a class of small noncoding RNA (ncRNA) molecules with a length of 18-24 nucleotides which play an essential regulative role for many cellular processes. Evidence suggests that the miRNome is a more precise and meaningful representation of a cell type and condition than the mRNA transcriptome. To identify miRNAs that are suitable for forensic body-fluid identification, a global screening by microarray analysis of c. 800 miRNAs of forensic blood and saliva samples was performed, and by bioinformatic processing, three differentially expressed candidate miRNAs for saliva and blood each were selected. The six candidates were then validated and confirmed via quantitative PCR. Herein, we present miRNA assays consisting of three differentially expressed miRNAs for the identification of blood (miR-126, miR-150, miR-451) and saliva (miR-200c, miR-203, miR-205), respectively. We conclude that miRNA extraction from forensic samples is possible and support a "proof of concept" that body-fluid identification by miRNA analysis may become a potent forensic technique., (© 2011 American Academy of Forensic Sciences.)

Sudden infant death syndrome (SIDS) constitutes a considerable percentage of infant death of unknown etiology. Individual catecholamine response variation is suspected to play a role in SIDS. TH01 is a tetrameric short tandem repeat marker in the tyrosine hydroxylase gene, which regulates gene expression and catecholamine production with allele 9.3 exerting a particularly strong effect on noradrenaline production. We investigated in an age-controlled study the TH01 allele frequencies in 127 cases of SIDS and 406 control cases to assess whether in SIDS cases a distinct TH01 allele distribution could be determined as has been reported by a previous study. We found that genotypes containing one or two 9.3 alleles were significantly more frequent in SIDS patients (58.2%) than in control subjects (48.4%, p=0.038), whereas all other alleles were more frequent in the control subjects. Our findings support the notion that there exists a significant association between TH01 gene configuration and SIDS., (© 2011 American Academy of Forensic Sciences.)

DNA extraction from and DNA typing of fresh water-exposed aged bone specimens poses a challenging task and is not very well examined. This study presents a new method to extract typable DNA from such problematic bone specimens. The procedure comprises low-heat drilling and cryogrinding, mild lysis conditions, and silica-column-based DNA cleaning. DNA quantity is assessed by quantitative PCR prior to short tandem repeat (STR) amplification. The procedure was employed with a 67-year-old tibia bone fragment recovered from a fresh water lake and succeeded to produce a full STR profile using the MPX-SP1 and MPX-SP2 mini-STR kits and a partial profile with 12 successfully amplified STRs using the Identifiler STR kit. The new method for the extraction of DNA from aged fresh water-exposed bone specimens presented herein was successfully applied to prepare DNA of sufficient quality and quantity to generate a full STR profile., (© 2010 American Academy of Forensic Sciences.)

Here we report a case where a discrete section of the cytological slide preparation of a female individual was obviously contaminated with pleura liquid of a female tumor patient. Analysis of the cancerous pleura liquid and the healthy cells of the slide preparation showed different DNA profiles, indicating that the material originated from two different female individuals. The DNA profile of the cell mixture revealed a heterogenous pattern whereby the alleles could be assigned to the healthy and the tumor patient. Loss of heterozygosity (LOH) was observed in four of eight short tandem repeat systems for the pleura liquid and the cell mixture. Despite the low amount of DNA on the slide preparation and the occurrence of LOH, it was possible to clarify the case and to support the assumption that a drop of cancerous pleura liquid contaminated the cytological slide.

Medical malpractice charges from 1989 to 2002 were evaluated. A rising number of cases during this period is evident. The charges of practice falling below the standard of care (n = 285) were surveyed to determine who informed the prosecution, which clinical subjects are involved, what kind of charges can be found and whether such allegations can be appropriately assessed by means of a forensic autopsy. Forensic pathologists were found to be useful for ascertainment and interpretation of autopsy findings. If special questions arise, an additional expert opinion should be suggested by the forensic pathologist. There was no relevant shift in the range of subjects involved compared to former studies. The investigated charges might represent only a small fraction of cases of medical practice falling below the standard of care.

In a postmortem exploratory study, we examined whether specific amino acid abnormalities associated with liver diseases in vivo may also be detected in human brain samples obtained at clinical autopsies. The branched-chain amino acids (BCAA: valine, leucine, isoleucine) were decreased in the group of patients with liver diseases compared with the control group, whereas the aromatic amino acids (AAA: phenylalanine, tyrosine) were increased. However, the ranges overlapped significantly and were not statistically different. The molar ratio BCAA/AAA was determined to be 1.92 in the collection of patients with liver diseases compared with 2.27 in the control group. In patients with liver disease, ornithine concentrations in the brain appeared significantly decreased whereas glutamine was significantly increased. No significant difference was found in the brain concentrations of proline. Amino acid analysis may contribute to the understanding of pathophysiological mechanisms of liver disease, which are discussed, and may supplement the postmortem diagnosis.

A remarkable case of complex suicide with poisoning and multiple self-inflicted gunshot wounds to the head is reported. After ingestion of a liquid insecticide, the victim shot himself twice in the head, once in each temple. Self-manufactured wooden dowels were used as projectiles in combination with conventional blank cartridges. The dowels had been glued on top of the blank cartridges and expelled by propellant gases. Moreover, the blank revolver used had been extensively manipulated in a rarely observed manner. Several occlusive devices had been removed from the barrel and the cylinder chamber to enable the expulsion of the wooden projectiles. The investigation of the methods used and the circumstances found at the scene pointed towards a planned complex suicide. A remarkable case with unusual projectiles, i.e., wooden dowels, fired by an extensively manipulated blank gun is reported, emphasizing the importance of close collaboration between the police firearm laboratory and forensic pathology in practical casework.

A report is given on an 8-year-old boy who suddenly and unexpected died. Autopsy findings point to acute heart failure. Microscopic examination of the heart showed increased interstitial and perivasal fibrosis and myocarditis with macrophage infiltration. Polymerase chain reaction (PCR) analysis for parvovirus B19 was positive in heart samples and in the spleen. Immunostaining for parvoviral surface antigens was negative. Although the virus does not appear to have infected the cardiomyocytes, we speculate that myocarditis arose from immunological cross-reaction to epitopes shared between the virus and the myocardium.

In a doping control case, a urine sample was tested positive for nandrolon. We were asked by the athlete to perform DNA investigations on the questioned urine sample and compare these to a fresh blood sample taken from the athlete in order to detect or rule out manipulation and/or switching of the samples. The urine sample had been collected nine months prior to the investigation and had been stored at 4 degrees C. In a first approach, nuclear DNA systems were investigated that failed with the exception of the Amelogenin system. Due to the high copy number of mitochondrial DNA molecules and the robustness of the mitochondrial genome, we investigated the HVR I and HVR II regions of mitochondrial DNA and obtained reproducible and clear sequencing results for both the blood and the urine samples. Due to the identical sequences, it could not be excluded that the blood sample and the urine sample were from the same individual or an individual having the same maternal lineage.

Genetic marker typing based on DNA amplification by the polymerase chain reaction (PCR) increasingly is being employed in forensic casework and for paternity testing. Allele frequencies were determined using PCR for 102 unrelated Germans (Rhine area) for the locus D18S51. Twelve alleles were observed, with frequencies ranging from 0.005 (allele 11) to 0.191 (allele 14). The observed heterozygosity was 0.867, and the power of discrimination was 0.968. There was no deviation from expectations under Hardy-Weinberg assumptions (P = 0.451).

For an evaluation of the survival period in morphine-involved deaths, changes of pulmonary histopathology were investigated in a total of 90 morphine-associated fatalities. Although pulmonary histopathology proved to be heterogeneous, several distinctive histological patterns emerged. While the subgroup with short courses of intoxication ( < 1 h, n = 15) was mostly characterized by slight/moderate alveolar edema (12/15), severe hemorrhages (12/15) and marked acute emphysema (9/15), the phenomena of massive edema (8/15), missing/slight hemorrhages (8/15) and absent/slight emphysema (11/15) dominated in the group with intermediate survival times (1-24 h, n = 15). Intravascular leukocyte accumulations (shock equivalent) occurred in the first group only once, but in the group with the longer survival time in 10 of 15 cases. Delayed deaths ( > 24 h, n = 4) were mainly characterized by purulent bronchitis/pneumonia. Those fatalities (n = 56) that could not be classified by anamnestic data were assessed by histological criteria. In comparison with the evaluation of the survival period by toxicological analyses, concordance was found in 46 cases. Pulmonary histopathology is not a tool for an exact graduation of survival time, but the combination of several key parameters can provide criteria for a differentiation between short ( < 1 h) and longer courses of intoxication.