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- Imigração em Portugal: contributo dos polimorfismos genéticos para a investigação de parentesco entre supostos familiaresPublication . Carvalho, Mónica; Vieira Da Silva, Cláudia; Dourado, Catarina; Dario, Paulo; Reis, Fátima; Rodrigues, Diogo; Porto, Maria João; Ribeiro, TeresaA solicitação de investigações de parentesco inseridas em processos de imigração, nomeadamente os relacionados com indivíduos que pretendem obter títulos de residência em Portugal, têm vindo a aumentar nos últimos anos no Serviço de Genética e Biologia Forenses da Delegação do Sul (SGBF S) O problema levanta se quando existe um familiar que já reside em Portugal, o qual pretende que outros familiares venham a residir também em Portugal e são apresentados documentos cuja veracidade é posta em causa Neste trabalho, apresentamos um caso em que o Ministério Público pretende confirmar a relação de parentesco biológico existente entre um determinado indivíduo e os seus três filhos registrais do sexo masculino,sendo que apenas dois deles são filhos da mesma mulher
- South Portugal population genetic analysis with 17 loci STRsPublication . Vieira da Silva, Cláudia; Cruz, C.; Ribeiro, Teresa; Espinheira, R.STRs are the standard genetic markers mainly used in forensic cases. In routine casework it is important to establish a population genetic database for further reliable statistical analyses. AmpF1STRIdentifiler (Applied Biosystems) and Geneprint Powerplex 16 (Promega Corporation, Madison WI, USA) are multiplex kits wich co-amplifie 17 STR - loci including the segment of X-Y homologous gene Amelogenina routinely used in our laboratory. 13 core short tandem repeat loci standardized under the combined DNA Index System (Codis): CSF1PO, D3S1358, D5S818, D13S317, D16S539, D18S51, D21S11, vWA, FGA, TH01, TPOX, two additional tetranucleotide loci - D2S1338 and D19S433 – and two additional pentanucleotides – Penta E and Penta D. The purpose of this study is to determine the allele distribution data of the 17 STR loci in 2445 caucasian unrelated individuals from the south of Portugal, 176 unrelated individuals from Cabo Verde and 102 unrelated individuals from Angola and compare it with the values of the all the population resident in the same area. Allele frequencies for each locus observed heterozygosity, expected heterozygosity, power of exclusion, power of discrimination, and p values of chi-square test for departures from Hardy-Weinberg expectations were calculated.
- Superfecundação heteropaterna na investigação de paternidadePublication . Ribeiro, Teresa; Vieira Da Silva, Cláudia; Dario, Paulo; Geada, Helena; Espinheira, Rosa
- Insertion/Delection Polymorphism and forensic aplications: A preliminary studyPublication . Vieira Da Silva, Cláudia; Matos, Sara; Amorim, António; Afonso Costa, Heloísa; Morais, Paulo; Santos, Rodolfo; Espinheira, Rosa; Santos, J. CostaThe human genetic identification is usually based on the study of STR markers, robust and reliable for samples containing relatively small quantities of DNA. Recent advances in forensic genetics have focused on the development of genotyping assays using shorter amplicons, in order to improve the successful amplification of degraded samples. Single Nucleotide Polymorphisms (SNP) and Insertion/Deletion polymorphisms (INDEL), length polymorphisms created by insertions or deletions of one or more nucleotides in the genome, have considerable potential in this kind of forensic samples, usually present in identification casework, since they can combine desirable characteristics of both, STR and SNP. In this study, a set of 30 biallelic Deletion/Insertion polymorphisms (DIP or INDEL) distributed over 19 autosomes plus Amelogenin in a single multiplex PCR reaction was applied to 100 healthy and unrelated caucasian individuals. Statistical analysis revealed that the 30 biallelic markers can provide satisfactory levels of informativeness for forensic demands.
- Necessidade de exumação em investigação de paternidadePublication . Ribeiro, Teresa; Eiras, Luisa; Dario, Paulo; Lucas, Isabel; Vieira Da Silva, Cláudia; Espinheira, Rosa
- Forensic genetic analysis of South Portuguese population with the six dye Powerplex® Fusion 6CPublication . Vieira Da Silva, Cláudia; Afonso Costa, Heloísa; Porto, Maria João; Cunha, E; Corte Real, F.; Amorim, AntónioAs an improvement in efficiency and in Human Discrimination Power, the new six dye multiplex kit PowerPlex® Fusion 6C System, by Promega, available for human identification can co-amplify 27 loci, in a single reaction, have been introduced in the last years with great success. This kit allows the amplification and detection of autosomal loci included in the expanded Combined DNA Index System CODIS, plus the loci Penta D, PENTA E and SE33 as well as Amelogenin for gender determination. Furthermore, this kit includes three Y –STRs (DYS391, DYS576 and DYS570), allowing allelic attribution in a total of 27 loci. This genetic markers extension satisfies not only CODIS but also European Standard Set recommendations. Thinking about continuous human migration movements, especially in a very cosmopolitan region like Lisbon and south of Portugal, and also, in keeping population studies and actualized STR databases we decided to update our previous studies. Our sample is composed of 600 unrelated individuals, from paternity testing with laboratory identity anonymised. DNA was extracted by Prep-n-go BufferTM(Thermo-Fisher Scientific). PCR amplification was performed with PowerPlex® Fusion 6C System, according to manufacturer’s guidelines. Fragment analysis was carried out in an Applied Biosystems® 3500 Genetic Analyser. Electrophoresis results were analysed with GeneMapper® ID-X v1.4. Allele frequencies and population statistics, including Hardy-Weinberg equilibrium p-values from exact test probabilities and forensic parameters were calculated with adequate software. In conclusion, our population information was updated in order to apply most recent data in our casework weight of evidence.
- Identificação genética a partir de lâminasPublication . Ribeiro, Teresa; Vieira da Silva, Cláudia; Lucas, Isabel; Dario, Paulo; Geada, Helena; Espinheira, Rosa
- Population Genetic Data for F13A01, FES/FPS, F13B and LPL in the South Portuguese PopulationPublication . Vieira da Silva, Cláudia; Amorim, António; Afonso Costa, Heloísa; Espinheira, Rosa; Costa Santos, JorgeDNA parentage testing is currently performed using several highly polymorphic short tandem repeats (STRs). In our routine casework, we apply two validated STRs kits, in order to have results in the 13 codis loci plus D2S1338, D19S433, PENTA E, PENTA D, and Amelogenin. In complex and deficient paternity cases it is often necessary to increment the number of studied STRs. For this reason, we introduced in our laboratory GenePrint® FFFL Multiplex kit, which can provide results in F13A1, FES/FPS, F13B, and LPL using the GenePrint® FFFL System (Promega, USA) kit. In this study, we analyzed 150 unrelated and healthy individuals from the south Portugal population. Allele frequencies and statistical parameters were estimated with Arlequin 3.5.1.2. Paternity Statistics were calculated using software package PowerStats v12. The forensic efficiency values suggested that loci F13A01, FES/FPS, F13B, and LPL are discriminative and very useful to solve complex forensic casework, and should be added to the set of STRs loci routinely used in Forensic laboratories. In conclusion, an additional 4 loci dataset was established for the south Portuguese population, which can be used for both forensic casework and complex kinship testing
- Investigação de parentesco biológico: a importância de marcadores adicionais em casos de especial complexidadePublication . Rodrigues, Diogo; Vieira Da Silva, Cláudia; Carvalho, Mónica; Afonso Costa, Heloísa; Sampaio, Lisa; Cunha, E; Corte Real, F.; Amorim, AntónioA grande maioria das perícias de investigação de parentesco biológico realizadas pelo Instituto Nacional de Medicina Legal e Ciências Forenses (INMLCF) têm inicio com a ordem do Tribunal para realização da mesma. O mais frequente é o Tribunal dar ordem para nos serem presentes, como intervenientes, um trio constituído por um suposto pai, uma mãe e um(a) filho(a), havendo, no entanto, variações quanto ao número ou tipo de intervenientes, o que pode resultar em maior dificuldade em apresentar resultados com a robustez desejada. Em qualquer dos casos, genericamente, as conclusões possíveis de um estudo de parentesco biológico e mais concretamente de um estudo de paternidade são a exclusão ou não exclusão de paternidade relativamente ao suposto pai em estudo. A conclusão pela não exclusão é sempre acompanhada pela valorização estatística dos resultados, designadamente através do cálculo e apresentação do Índice de Parentesco (IP) e da Probabilidade de Parentesco (W). No caso de uma perícia de investigação de parentesco em que nos seja presente unicamente um filho biológico do suposto pai e um suposto filho biológico, sem possibilidade de estudo das amostras das respetivas mães biológicas nem da amostra biológica do suposto pai, e nos é pedido o estudo sobre a possibilidade de ambos serem filhos biológicos do mesmo pai, a impossibilidade de exclusão da paternidade pode estar associada a valores calculados de IP que podem ser pouco robustos. O ensaio Investigator® HDplex permite o estudo de marcadores genéticos adicionais aos habitualmente estudados na rotina pericial do INMLCF.
- The role of DNA concentrations in forensic casework results : regression models applicationPublication . Vieira Da Silva, Cláudia; Amorim, António; Afonso Costa, Heloísa; Porto, Maria João; Corte Real, F.; Antunes, MariliaIn forensic DNA typing, short tandem repeats (STRs) are the most frequently genotyped markers in order to distinguish between individuals and to relate them to a crime or to exonerate the innocent. In recent years, new controversies have arisen with the advent of more sensitive techniques, allowing profiles to be recovered from minimum amounts of DNA, hence, bringing challenges to weight of evidence evaluation for forensic DNA profiles obtained from low template DNA samples. Introduction of interpretation models, or even new weight of evidence software should be accompanied by a measure of uncertainty that is part of any biological analysis. Specially, due to stochastic effects, the reliability of the obtained profiles might differ between machinery, workflow and also PCR settings in use in different laboratories. In this work we try to understand the relation between Peak Area, DNA concentration and also size marker, using adequate regression models. Buccal swabs from 180 individuals, with unknown identity, were selected for this study. DNA was extracted with prep-n-go™ buffer and quantified using Quantifiler® Trio DNA Quantification kit in a 7500 Real-Time PCR System (Applied Biosystems). STR amplification was performed with Powerplex Fusion 6C amplification kit (Promega). Amplified PCR products were separated and detected in an Applied Biosystems® 3500 Genetic Analyzer using manufacturer’s conditions. Electrophoresis results were analysed with GeneMapper® ID-X v1.4. Statistical analysis was performed with R Studio. Our results allow having an important overview about the relation between DNA concentrations, peak area, and size of the studied genetic markers.