Population genetics of the STR loci HUMCSF1PO, HUMF13A01, HUMFES/FPS and D12S391 in Asturias (northern Spain)

In order to use genetic loci in forensic identity testing, some population data are needed. This paper presents a report of allele frequency data for the loci HUMCSF1PO, HUMF13A01, HUMFES/FPS and D12S391 in a population sample from Asturias (northern Spain).No deviation from the Hardy-Weinberg equilibrium was detected in any of the four markers investigated and there was no evidence of association between the alleles of these loci. Statistical analysis was also carried out to obtain some parameters of medico-legal interest and comparative studies were carried out with other populations studied to date for these loci. The Asturian sample does not differ substantially from other Caucasian and Spanish populations.     

Validation of an ion-trap gas chromatographic-mass spectrometric method for the determination of cocaine and metabolites and cocaethylene in post mortem whole blood

The coingestion of cocaine (COC) and ethanol is a very frequent occurrence and is known to increase the risk of morbidity and mortality. The formation occurs of a transesterification product, the cocaethylene (CE), which is even more toxic than cocaine. In order to study the role of ethanol as an agent of interaction in lethal cocaine intoxication, and to establish its influence in post mortem cocaine concentrations, an ion-trap gas chromatographic-mass spectrometric method (GC-MS) was validated to quantify simultaneously the agent and its biotransformation products, benzoylecgonine (BE), ecgoninemethylester (EME) and the 'biomarker' of the interaction, the CE present in whole blood. Deuterated internal standards were added to 2 ml of post mortem whole blood and extracted in Bond Elut Certify columns. The residues were evaporated and derivatized with N-methyl-N-t-butyldimethylsilyltrifluoroacetamide (MTBSTFA). Detection was performed by electron impact ionization. The monitored ions were m/z 82/85 for EME-tert-butyldimethylsilyl (TBDMS)/EME-d3-TBDMS; m/z 182/185 for COC/COC-d3; m/z 196/199 for CE/CE-d3 and m/z 282/285 for BE-TBDMS/BE-d3-TBDMS. The limits of detection and quantification were found to be 25 ng and 50 ng ml(-1), respectively, for COC and CE, and 50 and 100 ng ml(-1) for BE and EME. Accuracy was different for each of the compounds, varying from 65 to 98%. The dynamic range of the assay was 50-2000 ng ml(-1).     

Ketamine in non-hospital and hospital deaths in New York City

We reviewed all ketamine-positive deaths (87) examined at the New York City Office of Chief Medical Examiner over a two-year period (1997 to 1999). There were 15 non-hospital deaths with 12 due to acute multidrug intoxications, one due to sarcoidosis, and two due to physical injury (blunt and thermal). In no instance was a fatal intoxication caused exclusively by ketamine. Opiates (10/15), followed by amphetamines (7/15) and cocaine (6/15), were the most frequent co-intoxicants. Ethanol was found in only one death. The race of all decedents was white and the majority were men (11/15) between the ages of 18 and 30 years. The remaining 72 instances of positive ketamine findings were hospital deaths following surgical procedures or burns.     

Data for Y-chromosome haplotypes defined by 17 STRs (AmpFLSTR Yfiler) in two Tunisian Berber communities

The 17 Y-chromosomal short tandem repeats (STRs) included in the AmpFLSTR Yfiler PCR Amplification Kit (AB Applied Biosystems) (DYS19, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS385, DYS437, DYS438, DYS439, DYS448, DYS456, DYS458, DYS635 and GATA H4) were typed in two Berber communities, a small village (Takrouna) and a town (Sejenane), from North Tunisia. As expected, diversity was higher in the town, even when compared with a pool of three small Berber communities, probably due to the combination of different founder effects and genetic drifts operating in the small villages.     

Nucleotide variability of HV-I in admixed population of the Brazilian Amazon Region

The analysis of genetic variation in the nucleotide sequences of mitochondrial DNA has been used as a tool in the study of history of different human populations, as Amerindians, Afro-descendents populations and furthermore admixed populations. In this study, the mitochondrial DNA was analyzed in 158 unrelated individuals in an admixed population of the Amazonian Region: Santarém-PA-Brazil. The polymorphisms were detected using both levels, analysis of restriction enzyme and direct sequencing. We observed a total of 49 different haplotypes were found determined by 46 variable nucleotides. The more frequent haplotypes (Hap03) was shared by five samples and 43 sequences were unique. The genetic diversity was estimated to 0.989+/-0.0067 and the probability of two random individuals showed identical mitochondrial DNA (mtDNA) haplotypes were 2.8%.     

A new method of age estimation based on the changes in human non-collagenous proteins from dentin

The new method exploits the characteristic of staphylococcal protease V8, which specifically splits peptide bonds where l-glutamic or l-aspartic acid participate. Those peptide bonds where d-aspartic acid is present remain unsplit because of the stereospecifity of enzymes. In accordance with expectations, fewer peptide bonds are split by this protease at more advanced ages and larger peptide fragments are thus formed due to the higher content of d-amino acid residues in the proteins of older people. The samples of acid-extracted non-collagenous proteins from dentin were separated using high performance liquid chromatography after enzymatic hydrolysis. A peak with a retention time of 45.3 min was chosen and his enlarging area showed a linear correlation with increasing age. Although the linear correlation with age was proved, the scattering of values decreases the usefulness of the proposed method for age estimation.     

Virological analysis in the diagnosis of sudden children death: a medico-legal approach

Infections are considered to be an important cause of unexpected death in children. It has also been assumed that respiratory viruses are involved in the genesis of sudden infant death syndrome (SIDS). The Spanish National Institute of Toxicology and Forensic Sciences act as the forensic reference centre for Spain. We analyse the experience of this centre in the virological study of 64 cases of sudden children death where viral serology, virological cultures, herpesviruses polymerase chain reaction (PCR) and electron microscopy were performed. According to pathological findings, death could only be attributed to an adenovirus infection in one amygdalitis with upper airways stenosis and asphyxia. Human herpes virus 6 (HHV-6) was detected by PCR in one case with pathological findings characteristic of SIDS. Recent infection by respiratory syncytial virus (RSV), Epstein-Barr virus (EBV) and cytomegalovirus (CMV) were also detected. Meanwhile, 85.9% of the cases yielded negative viral results. Twenty-eight infants were finally categorised as SIDS. Pathological findings of infection were detected in 12 patients despite the negativity of viral analyses. Although viral infection is an uncommon cause of sudden children death, a complete microbiological investigation will help to solve the puzzle of SIDS. Definitive guidelines for microbiological analyses need to be updated whilst new pathogens are discovered or new techniques are implemented in order to clarify unsolved cases.     

The involvement in sexual coercive behaviors of Spanish college men: prevalence and risk factors

This study aimed to know the prevalence of sexual coercion toward women perpetrated by acquaintance Spanish college men, and some personal factors associated with the involvement in these behaviors to replicate the confluence model. An anonymous questionnaire was completed by 196 university students that included an adaptation of the Sexual Experiences Survey, and other scales to assess different attitudes, motives, and experiences associated with sexual aggression. About 15% of men admitted some involvement in sexual behaviors when the woman did not want it. The control and dominance needs, the personal disposition to impersonal sex, and empathy competency showed the strongest association with the involvement in coercive sexual behaviors. Empathy moderated the effects of control and domination needs and the impersonal sex in predicting sexual coercion. Overall, our data supports the confluence model.