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Forensic DNA phenotyping (FDP) includes biogeographic ancestry (BGA) inference and externally visible characteristics (EVCs) prediction directly from an evidential DNA sample as alternatives to provide valuable intelligence when conventional DNA profiling fails to achieve identification. In this context, the application of Massively Parallel Sequencing (MPS) methodologies, which enables simultaneous typing of multiple samples and hundreds of forensic markers, has been gradually implemented in forensic genetic casework. The Precision ID Ancestry Panel (Thermo Fisher Scientific, Waltham, USA) is a forensic multiplex assay consisting of 165 autosomal SNPs designed to provide biogeographic ancestry information. In this work, a sample of 250 individuals from Rio Grande do Sul (RS) State, southern Brazil, apportioned into four main population groups (African-, European-, Amerindian-, and Admixed-derived Gauchos), was evaluated with this panel, to assess the feasibility of this approach in a highly heterogeneous population. Forensic descriptive parameters estimated for each population group revealed that this panel has enough polymorphic and informative SNPs to be used as a supplementary instrument in forensic individual identification and kinship testing regardless of ethnicity. No statistically significant deviation from Hardy-Weinberg equilibrium was observed after Bonferroni correction. However, seven loci pairs displayed linkage disequilibrium in pairwise LD testing (p < 3.70 × 10 -6 ). Interpopulation comparisons by F ST analysis, MDS plot, and STRUCTURE analysis among the four RS population groups apart and along with 89 reference worldwide populations demonstrated that Admixed- and African-derived Gauchos present the highest levels of admixture and population stratification, whereas European- and Amerindian-derived exhibit a more homogeneous genetic conformation., Competing Interests: Declaration of Competing Interest Authors declare they have no conflict of interest., (Copyright © 2023 Elsevier B.V. All rights reserved.)

In this work we present a retrospective study of 858 cases of paternity investigation performed in Rio Grande do Sul, Southern Brazil, from 2007 to 2012, where the alleged father was deceased or missing. These cases represent 3.3% (858/26187) of paternity tests performed in that period. Considering the analysis of 17 DNA short tandem repeat loci, we present here the proportion of cases with conclusive results according to the number of relatives of the unavailable alleged father investigated and their kinship. The results show 81.0% (695/858) of cases with conclusive results and their characteristics., (Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.)

Allele frequencies for 15 short tandem repeats (STR) loci were obtained from a sample of 2038 individuals undergoing paternity testing. The population is from Rio Grande do Sul, Brazil. The loci are the most commonly used in forensic and paternity testing, being analysed by the AmpFlSTR Identifiler (Applied Biosystems) commercial kit. The most polymorphic locus was D2S1338. Mutation rates were ascertained from this population sample. All the loci analysed reached the Hardy-Weinberg equilibrium. The results of genetic distance are consistent with the European-derived origins of Rio Grande do Sul population.