Mitochondrial DNA error prophylaxis: assessing the causes of errors in the GEP'02-03 proficiency testing trial

A qualitative and quantitative analytical method was developed and validated for the determination of 49 licit and illicit drugs in oral fluid. Small oral fluid samples, volume 1mL, were collected from volunteers using a modified Omni-Sal device and the analytes were extracted from an oral fluid/buffer mixture using a single Bond Elut Certify solid phase extraction cartridge. Liquid chromatography-tandem mass spectrometry (LC-MS-MS) and gas chromatography-repetitive full scan mass spectrometry (GC-MS) were used in parallel to analyze the extracts for the targeted drugs. Extracts were analyzed by GC-MS in their underivatized form and as their pentafluoropropionyl derivatives. Deuterated internal standards were used for quantification of drugs of abuse by LC-MS-MS to minimize matrix effects. Methadone-d(9) and tumoxetine were used as the internal standards for quantification of non-derivatized and derivatized analytes respectively by GC-MS. Linearity was demonstrated over the range 5-200 ng/mL and limits of detection were less than 4 ng/mL for each drug analyzed. The method demonstrated acceptable recoveries for most of the analytes and good intra- and inter-day precision. Acquisition of data by repetitive full scan GC-MS allows the addition of further analytes to the target menu.     

Population genetic data for 18 STR loci in Costa Rica

Allele frequencies for 18 STR autosomal loci (D3S1358, VWA, FGA, D8S1179, D21S11, D18S51, D5S818, D13S317, D7S820, D16S539, TH01, TPOX, CSF1PO, Penta D, Penta E, D19S433, D2S1338 and SE33) were obtained from a sample of 191-500 unrelated individuals from Costa Rica, Central America.     

Forensic analysis of black coral (Order Antipatharia)

Fourier-transform infrared spectroscopy (FTIR), discriminate analysis, X-ray fluorescence spectrometry (XRF), and stereoscopic microscopy were used to separate black coral forensic evidence items from similarly appearing items manufactured from plastics, bovid keratin, and mangrove wood. In addition, novel observations were made of bromine and iodine relationships in black coral that have not been previously reported.     

Where Do We Go from here?: Examining Intimate Partner Violence by Bringing Male Victims,Female Perpetrators,and Psychological Sciences into the Fold

Gender symmetry in intimate partner violence (IPV) has come to light in research, stirring much controversy. Historically, there has been resistance toward re-conceptualizing the problem from a psychology-informed framework, rather than from functional sociological discourse. Issues in examining IPV, with consideration of typologies, male victimization, and female perpetration, are discussed. Reporting, outcomes, revictimization, and perceptions of male victims and female perpetrators are addressed. An argument is offered for increased focus on psychological science, including theory and data from clinical, couple, and family systems disciplines, in addressing partner violence. A framework is provided for integrated, effective, and accurate approaches to IPV in discourse, policy, and service.     

Daily School Peer Victimization Experiences Among Mexican-American Adolescents: Associations with Psychosocial, Physical and School Adjustment

School bullying incidents, particularly experiences with victimization, are a significant social and health concern among adolescents. The current study extended past research by examining the daily peer victimization experiences of Mexican-American adolescents and examining how chronic (mean-level) and episodic (daily-level) victimization incidents at school are associated with psychosocial, physical and school adjustment. Across a two-week span, 428 ninth and tenth grade Mexican-American students (51 % female) completed brief checklists every night before going to bed. Hierarchical linear model analyses revealed that, at the individual level, Mexican-American adolescents’ who reported more chronic peer victimization incidents across the two-weeks also reported heightened distress and academic problems. After accounting for adolescent’s mean levels of peer victimization, daily victimization incidents were associated with more school adjustment problems (i.e., academic problems, perceived role fulfillment as a good student). Additionally, support was found for the mediation model in which distress accounts for the mean-level association between peer victimization and academic problems. The results from the current study revealed that everyday peer victimization experiences among Mexican-American high school students have negative implications for adolescents’ adjustment, across multiple domains.     

STR data for 11 autosomal STR markers from Costa Rica, Central America

Allele frequencies for 11 STR autosomal loci (F13A01, F13B, FESFPS, LPL, CSF1PO, TH01, TPOX, VWA, D16S539, D7S820 and D13S317) were obtained from a sample of 200 unrelated individuals from Costa Rica, Central America.     

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.