Comparative Analysis of the HV1 and HV2 Regions of Human Mitochondrial DNA by Denaturing High-Performance Liquid Chromatography

Abstract:  Denaturing high-performance liquid chromatography (DHPLC) was evaluated as a sequencing-independent means of detecting the presence of sequence differences in pair-wise mixtures of nonconcordant amplicons of human mitochondrial DNA (mtDNA). A total of 920 pair-wise combinations of HV1 and HV2 mtDNA amplicons from 95 individuals were assayed by DHPLC for sequence concordance/nonconcordance. For the 72 combinations of amplicons from different individuals who shared identical DNA sequences, DHPLC assays consistently indicated sequence concordance between the samples. This was in 100% agreement with sequencing data. For the 849 combinations of amplicons which differed in sequence, DHPLC detected the presence of sequence nonconcordance in all but 13 assays to yield 98.5% concordance with sequencing. Thus, DHPLC can be used to detect a diversity of sequence differences (transitions, transversions, insertions, and deletions) in the mtDNA D-loop. Accordingly, DHPLC may have utility as a presumptive indicator of mtDNA sequence concordance samples, as a screen for heteroplasmy/situational mixtures, and as a means for the physical fractionation of the individual contributors to an mtDNA mixture prior to sequencing.     

Methods of Choice in Completed Suicides: Gender Differences and Review of Literature

Abstract:  Suicide is an important public health hazard worldwide. A 4-year retrospective study from January 2000 to December 2003 was conducted to identify the favored methods in realized suicides among males and females in the west coastal region of India. During the study period, a total of 539 cases of suicidal deaths were autopsied. Males were predominantly affected (male: female—1.9:1). The age of the victims ranged from 13 to 90 years in males (mean = 40.1 years, median = 37.0 years) and 15 to 85 years in females (mean = 36.6 years, median = 32.0 years). Most favored method of suicide amongst males and females was hanging (36.9%, n  = 199) followed by poisoning (34.7%, n  = 187). Male dominance was apparent for each method of suicide except for self-immolation. Males were relatively more likely to use hanging and poisoning while females were more likely to prefer drowning and self-immolation as methods of suicide. Relatively younger females (mean   = 33.0 years, median = 32.0 years) preferred hanging as a method of suicide when compared to males (mean = 42.4 years, median = 40.0 years). Among females, significantly younger females resorted to hanging when compared to older females who preferred drowning. On investigating the various theories proposed for choice of suicide methods in males and females in different regions we conclude that preference of method of suicide in men and women is complexly determined. In this region, availability, accessibility, popularity, and socioacceptability seem to be the major determinants in the choice of methods among males and females rather than violence associated and lethality of the method. Females were as likely to use lethal and violent methods as males in this region.     

Handmade Guns in Trabzon, Turkey

Abstract:  A wide variety of handmade firearms have been involved in criminal cases in the city of Trabzon, Turkey. Although they are often very similar to commercially manufactured firearms in terms of design, loading and locking mechanisms, and cocking and firing arrangements, these guns are constructed from cheap materials and are not safe for firing. Handmade firearms manufactured in the Black Sea region of Turkey, particularly in the city of Trabzon, are similar to pistols manufactured by Browning, Luger, Star, Smith and Wesson, Berretta, and MAB. A total of 201 handmade guns referred to the Criminal Police Laboratories for examination from 2003 to 2005 were evaluated with respect to type, number of barrels, size and caliber, rifling, design, mechanism, operability, legality, and similarity to commercial models. We found that most of these handmade guns resembled commercial models in several aspects.     

Simple and Sensitive Method for Identification of Human DNA by Allele-Specific Polymerase Chain Reaction of FOXP2

Abstract:  The forkhead box P2 ( FOXP2 ) gene is specifically involved in speech and language development in humans. The sequence is well conserved among many vertebrate species but has accumulated amino acid changes in the human lineage. The aim of this study was to develop a simple method to discriminate between human and nonhuman vertebrate DNA in forensic specimens by amplification of a human-specific genomic region. In the present study, we designed an allele-specific polymerase chain reaction (PCR) using primers to amplify smaller than 70-bp regions of FOXP2 to identify DNA as being of human or nonhuman, including ape, origin. PCR amplification was also successfully performed using fluorescence-labeled primers, and this method allows a single PCR reaction with a genomic DNA sample as small as 0.01 ng. This system also identified the presence of human DNA in two blood stains stored for 20 and 38 years. The results suggested the potential usefulness of FOXP2 as an identifier of human DNA in forensic samples.     

Is Differentiation of Frequently Encountered Foreign Bodies in Corpses Possible by Hounsfield Density Measurement?

Abstract:  The radiological determination of foreign objects in corpses can be difficult if they are fragmented or deformed. With multislice computed tomography, radiodensities—referred to as Hounsfield units (HU)—can be measured. We examined the possibility of differentiating 21 frequently occurring foreign bodies, such as metals, rocks, and different manmade materials by virtue of their HU values. Gold, steel, and brass showed mean HU values of 30671–30710 (upper measurable limit), mean HU values for steel, silver, copper, and limestone were 20346, 16949, 14033, and 2765, respectively. The group consisting of objects, such as aluminum, tarmac, car front-window glass, and other rocks, displayed mean HU values of 2329–2131 HU. The mean HU value of bottle glass and car side-window glass was 2088, whereas windowpane glass was 493. HU value determination may therefore help in preautopsy differentiation between case-relevant and irrelevant foreign bodies and thus be useful for autopsy planning and extraction of the objects in question.     

An Investigation into Whether or Not the Class and Individual Characteristics of Five Turkish Manufactured Pistols Change During Extensive Firing

Abstract:  In order to assess whether or not the class and individual characteristics of a firearm change over time, five different makes of Turkish self-loading pistol were tested and were each fired a large number of times. The class and individual characteristics were identified for each pistol and the first fired cartridge case was compared with the subsequent consecutive 250th fired cases for each pistol. It was found that there were slight changes in some of the individual and class characteristics; however, this was not statistically significant and did not affect the ability of the firearms examiner to match the first fired case to the last fired case for each firearm tested.     

Suicide Among Children and Adolescents in a Province of Turkey

Abstract:  Despite well-documented increases in completed suicides among children, accurate knowledge of the characteristics of these suicides is very limited. The aim of this study was to investigate general characteristics of suicide among children and adolescents in the province of Istanbul and to evaluate obtained results in the light of the literature. Data were collected from autopsy records of the Morgue Department of Institute of Forensic Medicine, Istanbul. General characteristics of completed suicides among children and adolescents between 2001 and 2005 were retrospectively reviewed. The study included 176 suicides aged 9–19 years. The overwhelming majority of the suicides (92%) were aged 15–19 years. More than half of the suicides (60%) were male. The most frequent means of suicide was hanging (55%) followed by firearms (20%) and jump or descent from height (15%).     

Distinguishing Between Damage to Clothing as a Result of Normal Wear and Tear or as a Result of Deliberate Damage: A Sexual Assault Case Study

Abstract:  This paper focuses on bra damage, specifically damage observed in hook and eye fasteners that are generally located at the backstraps of bras. We describe bra design including the method by which hook and eye fasteners are generally constructed. We assess bra damage in two situations where the damage observed was unexpected given the case scenarios. These were: (i) the complainant of an alleged rape attributed damage to her bra hooks to force during a struggle and (ii) the complainant had earlier manipulated her bra hooks in an incident not related to her complaint. Steriomicroscopy and reconstruction experimentation were necessarily used to assess the bra damage. A systematic approach to damage analysis was employed by the forensic practitioners to correctly identify damage as being a result of mechanical manipulation and therefore as falsified. This paper suggests that more examples of falsified damage should be documented.     

Concordance Between the AmpFℓSTR® MiniFiler™ and AmpFℓSTR® Identifiler® PCR Amplification Kits in the Kuwaiti Population

Abstract:  The AmpFℓSTR^® MiniFiler™ polymerase chain reaction amplification kit, developed and supplied by Applied Biosystems, complements the AmpFℓSTR^® Identifiler^® polymerase chain reaction amplification kit (Applied Biosystems, Warrington, U.K.) by improving the success rate when profiling DNA that is degraded or contains inhibitors. Before applying the MiniFiler™ kit to casework, the profiles from 200 unrelated Kuwaitis were compared to Identifiler^® profiles. Concordance was observed for 99.875% (1598 of 1600) of the compared STR loci. The two discordant profiles displayed allelic dropout: one at the D13S317 locus due to nonamplification of allele 10 in the MiniFiler™ profile, and one at the D18S51 locus due to nonamplification of allele 18 in the Identifiler^® profile.     

Effects of Decomposition on Gunshot Wound Characteristics: Under Cold Temperatures with No Insect Activity

Abstract:  Information on gunshot wound characteristics has been well documented; however, there is little documented information on the effects of decomposition or environmental conditions on gunshot wound characteristics. This study was conducted in order to determine if decomposition would obscure or alter the physical surface characteristics of gunshot wounds when exposed to a low temperature environment. The study was conducted from November 2005 to January 2006 in Nova Scotia, Canada in forested and exposed environments, with air temperatures between −10°C and +10°C. Pigs were used as human models and were shot six times each at three different ranges (contact, 2.5 cm, and 1.5 m). Gunshot wound characteristics persisted until the wounds were covered with ice and snow, after which changes were observed. The changes were recognized as being unique to the different ranges of gunshots and it was concluded that changes due to decomposition under the conditions tested would not affect the collection and interpretation of gunshot wound evidence.