18 research outputs found
Second GHEP-ISFG exercise for DVI: “DNA-led” victims’ identification in a simulated air crash
The Spanish and Portuguese-Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) has organized a second collaborative exercise on a simulated case of Disaster Victim Identification (DVI), with the participation of eighteen laboratories. The exercise focused on the analysis of a simulated plane crash case of medium-size resulting in 66 victims with varying degrees of fragmentation of the bodies (with commingled remains). As an additional difficulty, this second exercise included 21 related victims belonging to 6 families among the 66 missings to be identified. A total number of 228 post-mortem samples were represented with aSTR and mtDNA profiles, with a proportion of partial aSTR profiles simulating charred remains. To perform the exercise, participants were provided with aSTR and mtDNA data of 51 reference pedigrees —some of which deficient—including 128 donors for identification purposes. The exercise consisted firstly in the comparison of the post-mortem genetic profiles in order to re-associate fragmented remains to the same individual and secondly in the identification of the re-associated remains by comparing aSTR and mtDNA profiles with reference pedigrees using pre-established thresholds to report a positive identification. Regarding the results of the post-mortem samples re-associations, only a small number of discrepancies among participants were detected, all of which were from just a few labs. However, in the identification process by kinship analysis with family references, there were more discrepancies in comparison to the correct results. The identification results of single victims yielded fewer problems than the identification of multiple related victims within the same family groups. Several reasons for the discrepant results were detected: a) the identity/non-identity hypotheses were sometimes wrongly expressed in the likelihood ratio calculations, b) some laboratories failed to use all family references to report the DNA match, c) In families with several related victims, some laboratories firstly identified some victims and then unnecessarily used their genetic information to identify the remaining victims within the family, d) some laboratories did not correctly use “prior odds” values for the Bayesian treatment of the episode for both post-mortem/post-mortem re-associations as well as the ante-mortem/post-mortem comparisons to evaluate the probability of identity. For some of the above reasons, certain laboratories failed to identify some victims. This simulated “DNA-led” identification exercise may help forensic genetic laboratories to gain experience and expertize for DVI or MPI in using genetic data and comparing their own results with the ones in this collaborative exercise.This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.Peer reviewe
Second GHEP-ISFG exercise for DVI: "DNA-led" victims' identification in a simulated air crash
The Spanish and Portuguese-Speaking Working Group of the International Society for Forensic Genetics (GHEP-ISFG) has organized a second collaborative exercise on a simulated case of Disaster Victim Identification (DVI), with the participation of eighteen laboratories. The exercise focused on the analysis of a simulated plane crash case of medium-size resulting in 66 victims with varying degrees of fragmentation of the bodies (with commingled remains). As an additional difficulty, this second exercise included 21 related victims belonging to 6 families among the 66 missings to be identified. A total number of 228 post-mortem samples were represented with aSTR and mtDNA profiles, with a proportion of partial aSTR profiles simulating charred remains. To perform the exercise, participants were provided with aSTR and mtDNA data of 51 reference pedigrees -some of which deficient-including 128 donors for identification purposes. The exercise consisted firstly in the comparison of the post-mortem genetic profiles in order to re-associate fragmented remains to the same individual and secondly in the identification of the re-associated remains by comparing aSTR and mtDNA profiles with reference pedigrees using pre-established thresholds to report a positive identification. Regarding the results of the post-mortem samples re-associations, only a small number of discrepancies among participants were detected, all of which were from just a few labs. However, in the identification process by kinship analysis with family references, there were more discrepancies in comparison to the correct results. The identification results of single victims yielded fewer problems than the identification of multiple related victims within the same family groups. Several reasons for the discrepant results were detected: a) the identity/non-identity hypotheses were sometimes wrongly expressed in the likelihood ratio calculations, b) some laboratories failed to use all family references to report the DNA match, c) In families with several related victims, some laboratories firstly identified some victims and then unnecessarily used their genetic information to identify the remaining victims within the family, d) some laboratories did not correctly use "prior odds" values for the Bayesian treatment of the episode for both post-mortem/post-mortem re-associations as well as the ante-mortem/post-mortem comparisons to evaluate the probability of identity. For some of the above reasons, certain laboratories failed to identify some victims. This simulated "DNA-led" identification exercise may help forensic genetic laboratories to gain experience and expertize for DVI or MPI in using genetic data and comparing their own results with the ones in this collaborative exercise.Depto. de Medicina Legal, Psiquiatría y PatologíaFac. de MedicinaTRUEpu
Rheumatoid Arthritis and its Association with HLA-DR Antigens. II. Antibodies to Native Connective Tissue Antigens Detected by Enzyme Linked Immunosorbent Assay
GHEP-ISFG proficiency test 2011: Paper challenge on evaluation of mitochondrial DNA results
The GHEP-ISFG Working Group performed a collaborative exercise to monitor the current practice of mitochondrial (mt)DNA reporting. The participating laboratories were invited to evaluate a hypothetical case example and assess the statistical significance of a match between the haplotypes of a case (hair) sample and a suspect. A total of 31 forensic laboratories participated of which all but one used the EMPOP database. Nevertheless, we observed a tenfold range of reported LR values (32–333.4), which was mainly due to the selection of different reference datasets in EMPOP but also due to different applied formulae. The results suggest the need for more standardization as well as additional research to harmonize the reporting of mtDNA evidence.Fil: Prieto, L.. Instituto Universitario de Investigación en Ciencias Policiales. Comisarıía General de Policía Científica; EspañaFil: Alves, Cíntia. Universidad de Porto; PortugalFil: Zimmermann, B.. Universidad de Innsbruck; AustriaFil: Tagliabracci, A.. Università Politecnica delle Marche. Dipartimento Scienze Biomediche e Sanità Pubblica, Medicina Legale; ItaliaFil: Prieto, V.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Montesino, M.. Instituto Universitario de Investigación en Ciencias Policiales. Comisarıía General de Policía Científica; EspañaFil: Whitte, M. R.. Genomic Engenharia Molecular; BrasilFil: Anjos, M. J.. National Institute of Legal Medicine; PortugalFil: Cardoso, S.. Universidad del País Vasco; EspañaFil: Heinrichs, B.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Hernandez, A.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Lopez Parra, A. M.. Universidad Complutense de Madrid; EspañaFil: Sala, Adriana Andrea. Universidad de Buenos Aires. Facultad de Farmacia y Bioquímica. Servicio de Huellas Digitales Genéticas; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Saragoni, V. G.. Legal Medicine Service. Forensic Genetics Unit; ChileFil: Burgos G.. Red Cross. Molecular Genetics Laboratory; EcuadorFil: Marino, Miguel Eduardo. Universidad Nacional de Cuyo. Facultad de Ciencias Médicas. Laboratorio de Análisis de ADN; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Paredes, M.. Instituto Nacional de Toxicología y Ciencias Forenses; EspañaFil: Mora Torres, C. A.. Instituto Nacional de Medicina Legal y Ciencias Forenses; ColombiaFil: Angulo, R.. Poder Judicial. Departamento de Ciencias Forenses; Costa RicaFil: Chemale, G.. Federal Police. National Institute of Criminalistics. Forensic Genetics Laboratory; BrasilFil: Vullo, Carlos. Equipo Argentino de Antropología Forense; Argentina. Laboratorio de Inmunogenética y Diagnóstico Molecular; ArgentinaFil: Sánchez Simón, M.. Citogen. Centro de Análisis Genéticos; EspañaFil: Comas, D.. Consejo Superior de Investigaciones Científicas; España. Universitat Pompeu Fabra; España. Instituto de Biología Evolutiva; EspañaFil: Puente, J.. LabGenetics; EspañaFil: López Cubría, C. M.. Guardia Civil. Departamento de Biología. Servicio de Criminalística; EspañaFil: Modesti, Nidia Maria. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Provincia de Córdoba. Poder Judicial; ArgentinaFil: Aler, M.. Institute of Legal Medicine of Valencia; EspañaFil: Merigioli, S.. Universidad de Porto; PortugalFil: Betancor, E.. Universidad de Innsbruck; AustriaFil: Pedrosa, D.. Nasersa; EspañaFil: Plaza, G.. Neodiagnóstica; EspañaFil: Masciovecchio, M. V.. IACA Laboratories; ArgentinaFil: Schneider, P. M.. Universitat Zu Köln; AlemaniaFil: Parson, Walther. Universidad de Innsbruck; Austri
A GEP-ISFG collaborative study on the optimization of an X-STR decaplex: data on 15 Iberian and Latin American populations
Abstract In a collaborative work carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG), a polymerase chain reaction multiplex was optimized in order to type ten X-chromosome short tandem repeats (STRs) in a single reaction, including: DXS8378, DXS9902, DXS7132, DXS9898, DXS6809, DXS6789, DXS7133, GATA172D05, GATA31E08, and DXS7423. Using this X-decaplex, each 17 of the participating laboratories typed a population sample of approximately 200 unrelated individuals (100 males and 100 females). In this work, we report the allele frequencies for the ten XSTRs in 15 samples from Argentina (Buenos Aires, Int J Legal Me