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Currently, autosomal Short Tandem Repeat (STR) markers represent the method of election in forensic human identification. Commercial kits of most common use nowadays –e.g. PowerPlex ® Fusion, Promega Corp.; AmpFlSTR GlobalFiler, Thermofisher scientific; Investigator 24Plex QS,Qiagen-, allow the co-amplification of 23 highly polymorphic STR loci providing a high discrimination power in human identity testing. However, in complex kinship analysis and familial database searches involving distant relationships, additional DNA typing is often required in order to achieve well-founded conclusions. The recently developed kit Investigator ® HDplex (Qiagen) co-amplify twelve autosomal STRs markers (D7S1517, D3S1744, D12S391, D2S1360, D6S474, D4S2366, D8S1132, D5S2500, D18S51, D21S2055, D10S2325, SE33), nine of which are not present in the above mentioned kits, providing a set of efficient supplementary markers for human identification purposes. In this study we genotyped a sample of 980 individuals from urban areas of ten Argentinean provinces using the Investigator ® HDplex kit, aiming to provide forensic estimates for use in forensic casework and parentage testing in Argentina. We report reference allelic frequency databases for each of the provinces studied as well as for the combined samples. No deviation of Hardy-Weinberg equilibrium was observed. A reasonable discrimination capacity and power of exclusion was estimated which allowed predicting an acceptable forensic behavior of this kit, either to be used as the main STR panel for simple cases or as an auxiliary tool in complex cases. Additionally, population comparison tests showed that the studied samples are relatively homogeneous across the country for these STR set. [ABSTRACT FROM AUTHOR]

We typed 1541 Y-STR haplotypes from reference samples along forensic casework investigations. In three haplotypes, we detected a variant allele designed as 16.3 at locus DYS533. This was confirmed by amplification using two commercial kits. Sanger sequencing revealing a novel motif corresponding to [TATC] 12 repeats with a 19-bp insertion in the flanking upstream region. We propose its origin as an insertion at − 9.1 upstream of the repeat motifs. We searched other local databases and found this allele in various geographical areas of Argentina and neighbouring countries. The haplotypes share a common core of 10 Y-STRs (DYS389-I/13; DYS389-II/30; DYS19/14; DYS481/22; DYS438/12; DYS437/16; DYS635/23; DYS392/13; DYS393/13; GATA H4/11) and belong to the R1b haplogroup. This 16.3 allele is restricted to southern South America, which allows us to propose a local and relatively recent origin. The sequence described herein constitutes a novelty that could be considered in future criteria for the nomenclature of STRs based on massively parallel sequencing. • Novel sequence structure at locus DYS533. • Upstream insertion explains a new variant allele DYS533/16.3. • New variant allele associated to south american Y haplotypes. [ABSTRACT FROM AUTHOR]

Abstract: We investigated nine Y-STRs on 1136 unrelated males from 10 provinces and three aboriginal tribes of Argentina. The urban populations depicted 654 different haplotypes (66%) and a haplotype diversity (HD) value of 0.9967. Meanwhile, the Amerindian groups ranged from 20 to 26 different haplotypes (62.5–38.2%) and the HD values from 0.8635 to 0.9586. By AMOVA it was determined a remarkable homogeneous haplotype distribution, nevertheless a certain degree of genetic substructure was detected in the North region, in particular in Salta population. Genetic distance allowed to identify three clusters one of them included Salta population and the Amerindian tribes. The results presented herein showed the impact of the European male genetic contribution on the aboriginal gene pool that can be, at present, assessed by analyzing the nowadays extant population. [Copyright &y& Elsevier]

Abstract: Allele frequencies, together with some parameters of forensic interest, for 15 STRs included in the Powerplex-16 System (CSF1PO, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S51, D21S11, FGA, Penta D, Penta E, TH01, TPOX and VWA) were estimated from a sample set of 1368 unrelated individuals from three of the most densely populated provinces of Argentina. No deviations from Hardy–Weinberg equilibrium were observed using the Bonferroni correction for the number of loci analyzed. Comparative analyses between our population data and that of other Argentinean databases previously published are presented and discussed. The most informative loci in our data set is the Penta E Loci with discrimination power larger than 0.98 and typical paternity index larger than 4.3. Our results demonstrate that these loci are robust since different laboratories and sample sets provided highly consistent results. This observation underscores the usefulness of these markers systems for human identification and parentage testing. [Copyright &y& Elsevier]

Abstract: The allele frequencies for the 15 short tandem repeats included in the Power Plex-16 kit (Promega Corp., Madison, WI, USA) were determined in a sample of 429 unrelated individuals from five provinces of the Northern and Northeastern regions of Argentina. Three Northern provinces including Salta, Formosa and Chaco and two within the region surrounded by the Paraná and Uruguay Rivers commonly known as the Argentine Mesopotamia, including Misiones and Corrientes. Since in this region Entre Ríos Province is also present, previously published results were used for comparison. The calculated parameters: polymorphism information content (PIC); discrimination power (DP); matching probability (MP); typical paternity index (TPI) and power of exclusion (PE) showed Penta E to be the most valuable marker from the studied sample set. All loci met Hardy–Weinberg expectations using the Bonferroni correction for the number of loci analyzed, except D3S1358 in Salta and THO1 in Formosa provinces. Population differentiation test revealed that the Salta population sample data denoted significant differences for various loci when compared with the other province information presented here in, as well as with other published data sets. [Copyright &y& Elsevier]

Abstract: Argentina is considered to be genetically heterogeneous, with important Native American and European genetic contributions to its extant population. In order to test if genetic sub-structure does exist in Argentina, a set of 15 autosomal markers were analyzed in 5282 individuals inhabiting ten provinces. Allele frequencies, Hardy–Weinberg equilibrium (HWE) and genetic distance, determined by F st, were established between the sampled populations. Our results indicate that the genetic distances are non-significant between most of the sampled populations, being Salta the only one with significant differences with almost all other populations (F st: 0.00486–0.01627, p: 0.0413–0.0002). Comparison between the ten populations investigated herein with already published data sets of six additional provinces was performed. This analysis showed that the genetic distances are non-significant between these sixteen provinces, with the exception of Salta sample. These results might suggest that genetic sub-structure cannot be detected by the autosomal STRs in the population of Argentina. Accordingly, a database of the whole country might be used for the correct interpretation of paternity testing and forensic casework results. [Copyright &y& Elsevier]

Abstract: The extant population of Argentina claims to be the most European country of Latin America. The statement has been held for over one century, and started when the Campaign Against the Dessert took place in 1870. This military mission was directed against the aboriginal communities in order to obtain their possessions. No scientific approach was available, till recent, for checking the supposed to be pure European ancestries. Uniparentally inherited genetic markers, such as mitochondrial DNA (mtDNA) and Single Nucleotide Polymorphisms (SNP) located in the non-recombinant regions of the Y-chromosome may clarify the strict European ancestry of the nowadays population of Argentina. A set of 325 unrelated males were chosen to evaluate if Amerindian markers such as the mitochondrial haplogroups A, B, C and D, as well as the C to T transition in locus DYS199 of the Y-chromosome were present. Its detection in the tested individuals might suggest an ancestral contribution of Amerindian lineages. Hypervariable Regions (HVR) I and II were sequenced by Big Dye termination approach and detected in automated platforms (ABI, 310 and 3100Avant). DYS199 C to T transition detection was carried out by primer specific PCR. Over 50% of the individuals tested carried either mtDNA or Y Amerindian markers, 10% both, 20% were of Amerindian patrilineage and less than 40% denoted non-Amerindian contribution in the uniparentally inherited markers. By this simple approach a different contribution can be suggested within the most European country of Latin America. [Copyright &y& Elsevier]

Abstract: Allele frequencies represent the basic tool for statistical evaluation of molecular studies based on DNA typing used in personal identification and forensic casework. To offer to the forensic and the molecular anthropology communities, a rapid access by Internet on-line inquires a STR reference database has been organized in the website www.ffyb.uba.ar/bdg. The database has a user-friendly access to the required information from each province of the country. On a karyotype scheme, it can be located from each of the thirteen CODIS markers and, on the Y chromosome, each of the minimal haplotype STRs were included initially at the www.yhrd.org. The frequencies are updated every September, except for the previous years in order to confirm previous calculations. In addition to the database that includes over 2700 genotypes, a complete list of references is included. Anonymous genotypes are included and most samples were obtained from routine casework. At present, over nine provinces are included and an additional support will be offered for aboriginal population data; that is, mainly well-defined ethnic groups typed either by autosomal and Y STRs as well as SNPs and mtDNA sequence data. Although it is completely free of charge, it requires registration before access. [Copyright &y& Elsevier]

Abstract: The population of Mendoza, like the entire population of Argentina, has a heterogeneous genetic constitution. It is the result of two major contributors; Native Americans and Europeans and, in a lesser degree, Western Africans, brought to the territory as slaves during colonial times. In order to investigate the proportion of genetic contributions of the parental populations to nowadays population of Mendoza, a set of 13 autosomal and 9 Y-STRs routinely used in forensic typing were selected. Although these markers are not the best suited for tracing ancestry, they might provide clues about the genetic structure of a population. A total of 242 male unrelated donors inhabiting Mendoza province were analyzed and compared with Argentinean Amerindian, Caucasian and African-American, reference samples. Genetic distance, based on R st values, and STRUCTURE analysis were performed for both polymorphic systems. Our results demonstrate a tri-parental genetic contribution whose proportions differs between autosomal or Y-STRs markers. Autosomal STRs denoted 46.8% European, 31.6% Native American and 21.5% African contributions. Instead, Y-STRs showed 67% European, 21% Amerindian, and 12% African ancestral lineages. These results are consistent with the history of submission undergone by the native populations during the conquest of the Americas and underscore the impact of the European male genetic contribution to extant population of Argentina. Probably our results underestimate the Caucasian and overestimate the Native American and African contributions since the polymorphisms employed are not as sensitive as the ancestry informative markers (AIMs). [Copyright &y& Elsevier]

Abstract: Allele frequency data of genetic markers employed in paternity testing and forensic casework is essential for the statistical analysis of the results obtained by these molecular markers. In 2004, our group developed and launched a free on-line reference database including autosomal STRs allele and Y-STR haplotype frequencies for 10 Argentinean provinces (http://www.ffyb.uba.ar/marcadores/antecedentes.asp). The dataset included 2710 individuals typed by means of 13 autosomal STRs and 239 individuals with the minimal Y-STRs haplotype (YHRD). In order to further improve the available information on-line, the database was increased for both autosomal and Y-STR markers. A total of 6501 genotypes from unrelated donors were added to the previous database. These samples were obtained from Buenos Aires, Chubut, Rio Negro, Santa Fe, Mendoza, Misiones, Corrientes, Chaco, Formosa and Salta, and typed at least with 13 autosomal STRs and 1336 unrelated males were also typed for Y-STRs. In parallel, protocols for DNA analysis and reference bibliography were updated. The present update attained a total of 9211 genotypes and 1575 Y-chromosome haplotypes from the Argentinean population. This contribution offers on-line statistical information about highly standardized genetic markers to the forensic and molecular anthropology research communities. [Copyright &y& Elsevier]

Abstract: The allele frequencies for 17autosomal short tandem repeats were determined in a sample of 1933 unrelated individuals from Mendoza, Argentina. The calculated parameters: polymorphism information content (PIC); discrimination power (DP); matching probability (MP); typical paternity index (TPI) and power of exclusion (PE), showed Penta E as the most valuable marker from the studied sample set. All loci met Hardy–Weinberg expectations using the Bonferroni correction for the number of loci analyzed. The mutation rate for these markers was analyzed by studying a total of 596 trio mother/son/father. We found a total of 14 mutations in different markers; all of them were single-step. [Copyright &y& Elsevier]

Abstract: A sample of 566 unrelated males from Mendoza province was typed for 12 Y-STRs loci, 237 of these males were typed for 17 Y-STRs. When analyzing only the minimal haplotype of 9 Y-STRs we found a total of 398 different haplotypes, of which 317 were unique, and the haplotype diversity was 0.9931. If we analyzed the 12 Y-STRs, which make up the extended haplotype, we observed that 87% of the total of 470 different haplotypes are unique, and the haplotype diversity was 0.9989. In the 237 males typed with 17 Y-STRs included in the AmpFISTR YFiler Amplification Kit (AB Applied Biosystems), we found 226 different haplotypes of which 96% are unique, and the most frequent haplotype appears only 3 times in the study population. On the other hand, in a total of 173 father/son pairs, mutations were observed in DYS389I/II, DYS385a/b, DYS439 and DYS458 markers. In addition, there were duplications on DYS19 and DYS437 markers. However, the mutation rates are similar to those already described. The comparison between our data and previous one from Mendoza, other Argentinean provinces and different world populations, reflected a similar haplotype distribution to that depicted by European populations. The most frequent haplotype is the modal for the European haplogroup R1b, this supports its European origin. [Copyright &y& Elsevier]

Abstract: The 12 Y-chromosome STRs included in the “minimal haplotype” plus “SWGDAM core set” (DYS438 and DYS439) and DYS437, were typed in 224 unrelated males from Mendoza province, Argentina. The amplifications were performed using PowerPlex®Y Systems (Promega Corp.) and AmpFISTR YFiler Amplification Kit (AB Applied Biosystems). A total of 203 different haplotypes were identified, of which 186 were unique and 17 were found in two or more individuals. Allele frequency and haplotype diversity (HD) were calculated. [Copyright &y& Elsevier]

Allele frequencies of 15 short tandem repeats (STRs) loci included in the PowerPlex 16 kit (Promega Corp., Madison, WI, USA) were obtained from a sample set of unrelated individuals inhabiting Rio Negro (N=593) and Chubut (N=320) provinces of the Argentinean Patagonia. Comparative analyses between our population data and other Patagonian Province (Neuquen) are presented.