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Abstract: During the military governments in Argentina in the 1970s, the bodies of people who had been detained and later killed were deposited in individual graves as well as common graves. The identity of the majority of the bodies was not provided. During 2008, the Argentine Forensic Anthropology Team (EAAF) processed nine bone fragments from bodies found in a group of graves in the Province of Buenos Aires. Nuclear DNA (nDNA) profiles were obtained by amplifying autosomal STRs (using the Identifiler®, Profiler® and COfiler® kits), Y-STR (Y-Filer®) and mini-STR using kits developed “in-house”. The mitochondrial DNA (mtDNA) HV1 and HV2 regions were also sequenced on the same bone samples. Blood samples were analyzed from 21 individuals who reported to the EAAF that they had a family member missing from the aforementioned time period. This study presents the results of the comparison made between the bone sample genetic profiles and those of the family members, based on the genetic marker used (STR, Y-STR and/or mtDNA) and on the proposed kinships for each hypothesis. From the 9 bone samples analyzed, a total of 8 individual skeletons were observed. Of those 8 individuals, 4 were identified through kinship analysis. [Copyright &y& Elsevier]

Abstract: In 2004, the investigation of an illegal, 30-year-old common grave in Avellaneda Cemetery, Buenos Aires, Argentina was resumed. There, skeletal remains were found of people who “disappeared” for political reasons during the military dictatorship in Argentina (1976–1983). Bone remains were found mixed up, without anatomical order, and therefore it was necessary to determine the minimum number of individuals represented. Bones were grouped in 10 skeletons according to anthropological criteria and as there was no certainty that the reassembling was correct, genetic analysis was carried out on different bone samples to ascertain the correct re-association. Commercial kits and miniSTR systems were used to analyze autosomic STR markers. Mitochondrial DNA analysis was performed in those samples where STR and/or miniSTR failed. From each skeleton, teeth and a piece of femur diaphysis were analyzed, and it was also necessary to examine a vertebra in two of them. From the results of genetic analysis, it was determined that the minimum number of people represented in the grave was more than expected; the results also allowed for the confirmation of the gender of each one by Amelogenin. It was proven that six skeletons had been correctly reassociated by their morphological characteristics, while the assembly of the remaining four had been erroneous. Four of the re-associated skeletons were identified by kinship analysis comparing their genetic profiles with reference samples from relatives. [Copyright &y& Elsevier]

Abstract: The use of miniSTR markers is a valuable tool in the forensic laboratory since it allows high-quality genetic profiles to be obtained on low copy number (LCN) or degraded DNA taken from different samples, such as cadaveric material, paraffin-embedded tissue, chewing gum, traces of saliva, pieces of cloth, cigarette butts, bone samples, etc. In addition, it is useful to have additional STR loci to solve paternity cases with one or more inconsistencies or to increase the amount of genetic information for incomplete family studies, where the genetic profile of the alleged father has to be reconstructed. Genetic frequencies and forensic parameters were calculated for 12 non-CODIS miniSTR loci (D20S480, D6S2439, D6S1056, D9S1118, D4S2639, D17S1290, D10S1248, D14S1434, D22S1045, D4S2364, D2S441 and D1S1677) from a total of 506 unrelated individuals from various provinces in the central region of Argentina (Cordoba, Buenos Aires, Salta, Entre Rios and Santa Fe). The application of these miniSTR markers allowed LR>1000 values to be obtained in kinship cases with incomplete families whose results had not been significant when using commercial kits. In conclusion, a database with Argentine population frequencies from these 12 miniSTR markers may be very useful in adding supplementary information for the forensic genetic laboratory. [Copyright &y& Elsevier]

Abstract: Mitochondrial DNA hypervariable regions I and II were sequenced from 403 unrelated Argentine individuals. The aim of this study was to create a population database as well as to identify the population diversity for this genetic marker by classifying it into haplogroups. The sequence polymorphisms of the HVI and HVII regions were determined by PCR and direct sequencing. The haplotypes found were checked by phylogenetic haplogroup analysis to decrease haplotype assignation errors and to avoid artificial recombination. We found 78 different haplogroups in this set of samples. A high percentage of haplotypes (53%) belong to European haplogroups due to the large flow of European immigrants from colonial times. However, we also observed a high percentage of haplotypes that belong to Amerindian haplogroups (39%), which were conserved through the female Amerindian population contribution. Furthermore, we found a small group of haplotypes with Sub-Saharan African origin (3.5%) due to the slave trade at the beginning of Argentina''s colonization. The sequences found showed that this set of samples has an abundant haplogroup diversity because of the European and Amerindian ethnic group contribution. [Copyright &y& Elsevier]

Abstract: Forensic laboratories must add as much genetic information as possible in order to solve the broadened variety of post-mortem paternity and kinship cases now routinely presented. Often, use of STR autosomal markers alone is not enough to reach a high discrimination power, especially when dealing with degraded post-mortem material or complex family pedigrees. In order to expand the set of genetic markers used to solve challenging cases, and since reference databases are required in forensic application, allele frequencies and forensic parameters for 38 InDel and 50 SNP binary markers were calculated from a sample of thirty (for SNPs) and fifty (for InDels) unrelated individuals from the two most populous cities of Argentina: Córdoba and Buenos Aires. DNA was extracted with a modified salting out procedure and amplification products were detected on an ABI 3130 Genetic Analyzer (Applied Biosystems). No significant deviations from Hardy–Weinberg expectations were found. In the analyzed sample, no pairwise linkage disequilibrium between InDels and SNPs was found neither among the 88 binary markers nor the 17 STR markers from commercial kits. Comparisons were also made with previously studied populations. The present database will be useful for forensic and paternity purposes for the above mentioned cities of Argentina. Moreover, these additional markers can help forensic laboratories to solve parentage testing as well as to improve the analysis of degraded DNA samples. [Copyright &y& Elsevier]

Abstract: Allele frequencies and forensic parameters for twelve miniSTR autosomal loci (D10S1248, D14S1434, D22S1045, D4S2364, D2S441, D1S1677, D20S480, D6S2439, D6S1056, D9S1118, D4S2639 and D17S1290) were calculated from a sample of 506 unrelated individuals from the Central-East Region of Argentina. No significant deviations from Hardy–Weinberg expectations were found. Furthermore, comparisons with other previously studied populations were made. These twelve miniSTR markers may help forensic laboratories in solving parentage testing as well as in typing degraded DNA samples. [Copyright &y& Elsevier]