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

Génetica Forense-DE359-201801

La Genética Forense es una rama de la genética que analiza la variabilidad en el ADN de cada individuo como medio de identificación. Al ser única esta información en cada individuo; valorada por medio de análisis probabilísticos con ayuda de la genética de poblaciones se convierte en una herramienta importante como prueba de identificación para la resolución de casos en procesos civiles y penales que involucran casos de Paternidad Homologación de evidencias en casos criminalísticos y también en proceso de identificación de Personas Desaparecidas por violación a los derechos humanos así como en casos de personas desaparecidas NN

Génetica Forense-DE359-201802

La Genética Forense es una rama de la genética que analiza la variabilidad en el ADN de cada individuo como medio de identificación. Al ser única esta información en cada individuo; valorada por medio de análisis probabilísticos con ayuda de la genética de poblaciones se convierte en una herramienta importante como prueba de identificación para la resolución de casos en procesos civiles y penales que involucran casos de Paternidad Homologación de evidencias en casos criminalísticos y también en proceso de identificación de Personas Desaparecidas por violación a los derechos humanos así como en casos de personas desaparecidas NN

Plan de negocio para la implementación de una cadena valor eficiente en atención de casos filiación, a través del servicio de prueba de ADN

Presenta la implementación de un laboratorio denominado ADN Soluciona que se encargará de la realización de pruebas de ADN y asesoría en el campo de filiación aplicada a la justicia, destinada a cubrir la necesidad de sus potenciales clientes respecto a sus dudas de filiación e identificación de manera oportuna y confiable. El éxito de este proyecto radica en una estrategia de eficiencia en costos, con el fin de lograr precios competitivos, lo que generaría mayor demanda en el público y el incremento en el volumen, por medio de la diversificación del servicio (filiación e identificación), y en asociación estrategia con una de las fábricas que proveen de los insumos usados para el proceso de filiación. Actualmente existe un mercado potencial de 6,241 casos judiciales de filiación no atendidos con un valor de mercado potencial no atendido de S/.8,126,300; y en el caso del servicio de identificación en dúos Madre-Hijo (rubro aun no explotado por los competidores), se ha estimado que existe un potencial mercado de 19,252 casos con un valor de mercado no atendido de S/.3,198,400. El principal inconveniente para el público es el precio, el cual actualmente asciende a S/.1,200 , por tanto; dado que la estrategia de ADN Soluciona es la ventaja en costos, al adquirir directamente los insumos del proveedor del exterior, se logrará obtener un precio menor, y al ser más accesible al público, se lograría cubrir gran parte de la demanda no atendida en el país. Por lo explicado anteriormente, se analizó la viabilidad financiera del proyecto obteniendo un valor positivo de VAN de S/.880,271 y una TIR de 24,28% la cual es superior a la tasa WACC que espera el accionista, por lo tanto es un proyecto viable dentro de un proyección conservadora para los años que se han considerado el mismo.Tesi

Population Genetic Structure of Traditional Populations in the Peruvian Central Andes and Implications for South American Population History

Molecular-based characterizations of Andean peoples are traditionally conducted in the service of elucidating continent-level evolutionary processes in South America. Consequently, genetic variation among “western” Andean populations is often represented in relation to variation among “eastern” Amazon and Orinoco River Basin populations. This west-east contrast in patterns of population genetic variation is typically attributed to large-scale phenomena, such as dual founder colonization events or difffering long-term microevolutionary histories. However, alternative explanations that consider the nature and causes of population genetic diversity within the Andean region remain underexplored. Here we examine population genetic diversity in the Peruvian Central Andes using data from the mtDNA first hypervariable region and Y-chromosome short tandem repeats among 17 newly sampled populations and 15 published samples. Using this geographically comprehensive data set, we first reassessed the currently accepted pattern of western versus eastern population genetic structure, which our results ultimately reject: mtDNA population diversities were lower, rather than higher, within Andean versus eastern populations, and only highland Y-chromosomes exhibited significantly higher within-population diversities compared with eastern groups. Multiple populations, including several highland samples, exhibited low genetic diversities for both genetic systems. Second, we explored whether the implementation of Inca state and Spanish colonial policies starting at about ad 1400 could have substantially restructured population genetic variation and consequently constitute a primary explanation for the extant pattern of population diversity in the Peruvian Central Andes. Our results suggest that Peruvian Central Andean population structure cannot be parsimoniously explained as the sole outcome of combined Inca and Spanish policies on the region’s population demography: highland populations difffered from coastal and lowland populations in mtDNA genetic structure only; highland groups also showed strong evidence of female-biased gene flow and/or efffective sizes relative to other Peruvian ecozones. Taken together, these findings indicate that population genetic structure in the Peruvian Central Andes is considerably more complex than previously reported and that characterizations of and explanations for genetic variation may be best pursued within more localized regions and defined time periods