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Pampa Grande (PG) y Los Amarillos (LA) son dos sitios arqueológicos del noroeste argentino (NOA), en los que el estudio de ADN antiguo ha permitido determinar el sexo de los individuos y analizar los linajes paternos y maternos presentes. PG (Salta) se ha adjudicado al Período Formativo y LA, ubicado en la Quebrada de Humahuaca (Jujuy), habría tenido una masiva ocupación hacia el Período de Desarrollos Regionales. El objetivo de este trabajo es comparar ambos sitios en cuanto a su diversidad genética analizando los haplogrupos y haplotipos de ADN mitocondrial estudiados en dichas poblaciones. Se incluyeron en el análisis 19 individuos de PG y 18 de LA. Al analizar los linajes mitocondriales, se observa que los únicos haplogrupos compartidos entre ambas poblaciones son los haplogrupos A2 y D1, encontrados habitualmente en poblaciones amerindias. Por otro lado, no se detectó el haplogrupo B2 en LA, ni el C1 en PG. Los análisis de variación génica realizados a partir de la Región Hipervariable I indican una diferenciación genética significativa entre ambos sitios, siendo PG el más variable. Mecanismos microevolutivos asociados a la distancia geográfica y temporal parecen haber moldeado la diversidad intra e interpoblacional entre estos dos sitios prehispánicos del NOA.

El objetivo de este estudio consistió en: 1) determinar haplogrupos de ADNmt en restos esqueletales precolombinos de Pampa Grande, Prov. de Salta, Argentina, y 2) comparar los resultados obtenidos respecto de los registrados en poblaciones nativas extintas y actuales de la Argentina. A partir de muestras de hueso compacto de 21 individuos se logró, en 16 de ellos (76%), extraer, amplificar y secuenciar la región hipervariable I del ADNmt. Se observaron 17 sitios polimórficos y los porcentajes de los haplogrupos fueron los siguientes: A=6%, B=50%, C=0% y D =44%. Las elevadas frecuencias de los haplogrupos B y D son concordantes con las detectadas en poblaciones aborígenes actuales de la Argentina (B=38%, D=32%). El dendrograma obtenido revela que Pampa Grande se une al conjunto de las poblaciones del Chaco (Chorote, Toba, Chulupi) y a los mapuche de origen andino y se separa de los grupos extintos de Tierra del Fuego, probablemente, por la ausencia en estos de los haplogrupos A y B. Se discuten posibles causas determinantes de las relaciones y afinidades biológicas observadas.

The post-mortem interval (PMI) is the time elapsed between the death of an individual and its forensic examination. It is a crucial information for judicial authorities, but current techniques still cannot establish a precise time interval. Novel approaches are therefore required. Recently, gingival tissue has emerged as interesting for forensic analysis thanks to the protection offered by lips to this tissue, limiting the influence of environmental factors. It is also easily accessible, and its sampling is minimally invasive even in the presence of rigor mortis. Moreover, the expression of HIF-1α, a master mediator of the hypoxic environment, has been described in gingival samples at different post-mortem (PM) times. We have hypothesized that the time-dependent post-mortem expression of HIF-1α could serve as a biomarker to more accurately predict the PMI. Our analyses were performed in an animal model, the mouse, where environment can be precisely controlled. Therewith, gingival tissue morphology was evaluated through histochemical staining and HIF-1α expression was analyzed by qPCR, western blots and immunofluorescence at different post-mortem times (0h to 100h). Our results showed (a) a global post-mortem stability of gingival tissue (b) a rapid increase in HIF-1α mRNA expression in the short post-mortem times followed by a slow decrease in transcript expression until 100h PM (c) an expression of the HIF- 1α protein and its degradation products, that follows the mRNA pattern (d) the presence of HIF-1α protein in the epithelial and connective layers of the tissue, with signal accumulation in both gingival strata until at least 32h post-mortem. This pilot study thus validated the mouse and the gingival tissue as models for post-mortem analyses, as well as for studying the fate of proteins such as HIF-1α. Transferring these approaches to human subjects may provide a more accurate estimate of PMI. [ABSTRACT FROM AUTHOR]

"I still don't realize that he's dead.... I cried over it. It makes me sad to know that he was buried unaccompanied on his last trip. We were all shocked." This testimony corresponds to a family whose relative was buried in an anonymous grave 6 months after his disappearance was reported to the police. It is estimated that between 1 000 and 3 000 unidentified bodies are buried in anonymous graves in France each year. Most of these decedents have passed through the medico-legal system. However the identification of these bodies, outside the context of mass disasters, remains a complex problem. Several national and international publications have highlighted the prevalent problem of unidentified burials and the consequences for families who do not know the fate of their loved ones, specifically, whether they are alive or deceased. This 6-year retrospective study (2018–2023), covering a total of 2 324 unidentified decedents admitted to the Institute of Medical-Legal Paris (IMLP), aimed to assess the impact of the identification protocol implemented in 2017 on the number of bodies that remain unidentified (n  = 164). In addition, this study aimed to establish profiles for individuals who remained unidentified with the objective of identifying the factors that hinder their identification and developing correlated methods to address these issues. The results of this study were compared with other published studies to highlight the global problem and the ongoing need for collaboration between forensic practitioners and relevant authorities. Key points Despite great advances in human identification, unidentified decedents remain a global problem. This 6-year overview study covering a total of 2 324 unidentified bodies admitted to the IMLP provided relevant information about the unidentified decedent population and assessed the impact of a protocol established in 2017 on the rate of deceased buried without identity in Paris. The need to establish a national database in France to properly document and disseminate information on missing persons and to centralize the biological profile of unidentified bodies is key, as without antemortem information or a biometric database there can be no matching. [ABSTRACT FROM AUTHOR]