Results of the 2003-2004 GEP-ISFG collaborative study on mitochondrial DNA: focus on the mtDNA profile of a mixed semen-saliva stain

We report here a review of the seventh mitochondrial DNA (mtDNA) exercise undertaken by the Spanish and Portuguese working group (GEP) of the International Society for Forensic Genetics (ISFG) corresponding to the period 2003-2004. Five reference bloodstains from five donors (M1-M5), a mixed stain of saliva and semen (M6), and a hair sample (M7) were submitted to each participating laboratory for nuclear DNA (nDNA; autosomal STR and Y-STR) and mtDNA analysis. Laboratories were asked to investigate the contributors of samples M6 and M7 among the reference donors (M1-M5). A total of 34 laboratories reported total or partial mtDNA sequence data from both, the reference bloodstains (M1-M5) and the hair sample (M7) concluding a match between mtDNA profiles of M5 and M7. Autosomal STR and Y-STR profiling was the preferred strategy to investigate the contributors of the semen/saliva mixture (M6). Nuclear DNA profiles were consistent with a mixture of saliva from the donor (female) of M4 and semen from donor M5, being the semen (XY) profile the dominant component of the mixture. Strikingly, and in contradiction to the nuclear DNA analysis, mtDNA sequencing results yield a more simple result: only the saliva contribution (M4) was detected, either after preferential lysis or after complete DNA digestion. Some labs provided with several explanations for this finding and carried out additional experiments to explain this apparent contradictory result. The results pointed to the existence of different relative amounts of nuclear and mtDNAs in saliva and semen. We conclude that this circumstance could strongly influence the interpretation of the mtDNA evidence in unbalanced mixtures and in consequence lead to false exclusions. During the GEP-ISFG annual conference a validation study was planned to progress in the interpretation of mtDNA from different mixtures.     

Population frequency for the short tandem repeat loci D18S849, D3S1744, and D12S1090 in Caucasian-Mestizo and African descent populations of Colombia

Blood samples from 489 unrelated Caucasian Mestizo and 252 individuals of African descent in Colombia were amplified and typed for three short tandem repeat (STR) markers (D12S1090, D3S1744, and D18S849). All markers conformed to Hardy-Weinberg equilibrium expectations in both populations studied. In addition, heterozygosity, mean exclusion chance, polymorphism information content, discrimination power, and the assumption of independence within and between loci were determined. The mean exclusion chance for all three STR markers is 0.9750 in the Caucasian Mestizo population and 0.9731 in the African Colombian Population. The discrimination power is 0.999925 and 0.999911 in the Caucasian Mestizo and African Colombian respectively.     

美国法学教育的概况

我很荣幸能占用《法学》的篇幅向中国法律界的同行介绍一些美国法律教育的情况。中美两国虽然在社会制度有许多不同点,但可以在法律方面相互取长补短。年青的中国社会     

Exploratory study on classification and individualisation of earprints

The FearID research project is aimed at the individualisation of earprints for the purpose of forensic research. The study presented here was carried out within the framework of this project. It intends to combine a review of what is known from literature on the classification and individualisation of earprints with results from a preliminary study of earprints. Possibilities for, and limitations to, the use of earprints in forensic investigation are addressed. Differences between eliminating a suspect, placing a suspect at a crime scene, and linking crimes by prints left at different scenes are considered.     

Rice farming in Bali: organic production and marketing challenges

All is not well with agriculture in Southeast Asia. The productivity gains of the Green Revolution have slowed and even reversed and environmental problems and shortages of water and land are evident. At the same time changing world markets are shifting the dynamics of national agricultural economies. But from the point of view of farmers themselves, it is their season-to-season economic survival that is at stake. Bali is in some ways typical of other agricultural areas in the region, but it is also a special case because of its distinctive economic and cultural environment dominated by tourism. In this environment, farmers are doubly marginalized. At the same time the island offers them unique market opportunities for premium and organic produce. This article examines the ways in which these opportunities have been approached and describes their varying degrees of success. It focuses especially on one project that has been successful in reducing production costs by conversion to organic production, but less so in marketing its produce. It argues finally for the need for integrated studies of the entire rice production/marketing complex, especially from the bottom-up point of view of farmers.     

Grouping of ammunition types by means of frequencies of occurrence of GSR

An attempt was made to build a classification scheme for gunshot residues (GSR) samples originating from four types of ammunition, collected from shooters' hands immediately after shooting. The secured material was examined with the use of SEM-EDX method in the automatic manner. The obtained results were expressed as frequencies of occurrence of particles assigned to various chemical classes. In order to establish the most discriminative of these features the Mann-Whitney test was performed. Cluster analysis was performed for grouping the analysed samples according to their origin, i.e. the type of ammunition. It has been found that samples of GSR originating from Browning 7.65 mm and Luger 9 mm ammunition can be fairly easy differentiated from the remaining samples, whereas samples of GSR originating from of Makarov 9 mm and these of Tokarev 7.62 mm could not be differentiated using frequencies of occurrence of particles in the selected chemical classes.     

Examination reports on survived strangulation cases

Clinical-forensic examination of strangulation victims is an increasing part of the routine of many forensic pathology institutes. The cases examined between 2004 and 2008 at the Institute of Legal Medicine of the Hanover Medical School were retrospectively analysed. In total, the study material comprised 218 victims (175 females and 43 males). In 80.7 %, the clinical-forensic examination was performed within 24 hours after the incident. In the overwhelming number of cases, the alleged perpetrator was no stranger. 128 victims (58.7 %) had strangulation marks, 32 victims (14.7 %) ligature marks and 65 victims (29.8 %) nail marks. Four victims showed injuries of the laryngeal and pharyngeal structures (reddening, hematomas, swelling and in one case a fracture of the cricoid cartilage on both sides). Extensive petechiae were predominantly seen in the conjunctivae, the buccal mucosa and the skin of the face in cases where the victims suffered a loss of consciousness. 87 cases (39.9% were classified as potentially life-threatening and 30 cases (13.8 %) as acute life-threatening events. This classification is of legal relevance for the penalty. In addition, 60 victims experienced sexual violence. These results suggest that early clinical-forensic examination is crucial for documenting forensic evidence in support of police investigations and may deliver significant details relevant in court.     

Homicide in Adana, Turkey: a 5-year review

Violence is a significant public health problem. Thus, so as to prevent this problem, homicide, the severest form of violence depriving a human being of his right to live, deserves a detailed examination. This study is a retrospective research examining the 2951 cases of medicolegal autopsies in Adana during a period of 5 years (1997-2001). Among these cases, 620, which were determined to be homicidal, were taken into the scope of this study. The cases were examined with respect to sex, age groups, the method used during the act of homicide, the number and the localization of the wounds on the body. A total of 620 (21%) of the medicolegal autopsies conducted within this period were homicides. Of these cases, 515 (83.06%) were male and 105 (16.94%) female, and the rate of the males to females was 4.9; 72.74% of the victims were between the ages of 21 and 50. It was seen that 54.83% of the homicides involved firearms, while 35.16% of the victims were stabbed to death with a cutting object. It was also determined that the victims suffered a single wound in 47.35% of firearm-related murders and 29.35% of stabbings resulted in death. Alcohol was found in the blood of 7.58% of the homicide victims, while none had any illicit drugs.