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  • Imigração em Portugal: contributo dos polimorfismos genéticos para a investigação de parentesco entre supostos familiares
    Publication . Carvalho, Mónica; Vieira Da Silva, Cláudia; Dourado, Catarina; Dario, Paulo; Reis, Fátima; Rodrigues, Diogo; Porto, Maria João; Ribeiro, Teresa
    A 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 STRs
    Publication . 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 paternidade
    Publication . Ribeiro, Teresa; Vieira Da Silva, Cláudia; Dario, Paulo; Geada, Helena; Espinheira, Rosa
  • Analysis of 17 STR data on 5362 southern Portuguese individuals-an update on reference database
    Publication . Cabezas Silva, Raquel; Ribeiro, Teresa; Lucas, Isabel; Porto, Maria João; Costa Santos, Jorge; Dario, Paulo
    The main objective of this work consisted of the updating of allele frequencies and other relevant forensic parameters for the 17 autosomal STR loci provided by the combination of the two types of kits used routinely in our laboratory casework: AmpF/STR Identifiler(®) and the Powerplex(®) 16 Systems. This aim was of significant importance, given that the last study on these kits within the southern Portuguese population dates back to 2006, and, as a consequence, it was necessary to correct the deviation caused by population evolution over the last ten years so that they might be better applied to our forensic casework. For this reason genetic data from 5362 unrelated Caucasian Portuguese individuals from the south of Portugal who were involved in paternity testing casework from 2005 to 2014 was used. Of all the markers, TPOX proved to be the least polymorphic, and Penta E the most. Secondly, this up-to-date southern Portuguese population was compared not only with the northern and central Portuguese populations, but also with that of southern Portugal in 2006, along with populations from Spain, Italy, Greece, Romania, Morocco, Angola and Korea in order to infer information about the relatedness of these respective populations, and the variation of the southern Portuguese population over time.
  • Necessidade de exumação em investigação de paternidade
    Publication . Ribeiro, Teresa; Eiras, Luisa; Dario, Paulo; Lucas, Isabel; Vieira Da Silva, Cláudia; Espinheira, Rosa
  • Identificação genética a partir de lâminas
    Publication . Ribeiro, Teresa; Vieira da Silva, Cláudia; Lucas, Isabel; Dario, Paulo; Geada, Helena; Espinheira, Rosa
  • QUANTIFILER®TRIO DNA method performance in a collection of ancient samples
    Publication . Vieira- Silva, C.; Lopes, J.; Afonso Costa, H.; Ribeiro, T.; Porto, M.J.; Dias, M; Cunha, E; Amorim, A,
    During the past few years significant progress has been made in solving technical challenges associated with STR profiling including the ability to analyze degraded DNA and low amounts of DNA. The result of these changes is that useful STR profiles can now be obtained from previously untypeable forensic DNA samples. Analysis of DNA from ancient material represents an important role in molecular anthropology, although there are many limitations concerning low DNA quantity and/or degraded DNA, and/or PCR inhibitors. These factors can make it difficult to decide whether to continue with STR analysis, which STR panel to use and how much DNA to add to PCR reaction. With all these constraints, DNA quantification represents an important tool to decide which method will follow in order to improve workflow and have good results in less time-consuming. The Quantifiler® Trio DNA method provides a quality index (QI) to detect the presence of degraded DNA along with PCR inhibitors.This guide allows the selection of the optimal short tandem repeat (STR) analysis chemistry (autosomal, or miniSTR) and streamlines the workflow while increasing downstream analysis success rates. In order to compare DNA quality from different extraction methods, samples from 46 exhumed Middle Ages individuals were extracted with modified phenol-chloroform method and also PrepFiler Express BTA™ method. DNA was quantified with Quantifiler® Trio DNA Quantification in an Applied Biosystems® 7500 Real-Time PCR System. Results were analyzed and allow us to point Quantifiler® Trio method as an important tool in pre-STR typing methods in ancient samples
  • Got her mummy´s eyes: Eye color investigation using IrisPlex – preliminary study
    Publication . Dario, Paulo; Rita Olivera, Ana; Ribeiro, Teresa; Lucas, Isabel; Marques, Manuela; Porto, Maria João; Costa Santos, Jorge; Corte Real, F.; Dias, Deodália
    SNP phenotypic markers are being studied by several groups worldwide. As a result, phenotypic loci such as the ones responsible for human eye, hair and skin color are starting to get known. These may provide information for identification of unknown sample donors in criminal casework when there are no suspects. This kind of information may be even more relevant when the sample donor possesses phenotypic characteristics which distinguish him from the population in which he is inserted. Nevertheless, this approach may be used in similar scientific areas. In this work, a DNA sample from a mummified corpse with historical and scientific interest was studied in order to discover more information about who this corps belonged to. One of the tools used in this investigation was IrisPlex, designed for eye color prediction. This study presents one example on how this methodologies may be useful, not only in forensic investigation but also in areas such as physical anthropology.
  • Y-Filer Plus® genetic characterization of caucasian individuals from South Portugal
    Publication . Vieira da Silva, Cláudia; Afonso Costa, Heloísa; Proença, Marta; Ribeiro, Teresa; Porto, Maria João; Amorim, António
    Due to their paternal inheritance, Y-STRs offers particular perspectives for identification and kinship analysis and are also a precious tool in sexual assault cases with relatively high amount of female DNA and also in mixtures from multiple male donors. Nonetheless their value, there are some limitations to their use in forensic investigations since their ability to discriminate between individuals is considerably lower than that of the autosomal STRs set, mainly in cases with close or distant patrilineal relatives.One of the most recently developed Y-STR kit, Y-Filer Plus® (Life Technologies, Foster city, USA), allows forensic geneticists to study 27 Y-chromosomal loci. All the 16 markers included in the Y-Filer® kit (Life Technologies, Foster city, USA), plus 9 additional markers: DYS576, DYS627, DYS460, DYS518, DYS570, DYS449, DYS481, DYF387S1 and DYS533, six of which (DYS576, DYS627, DYS518, DYS570, DYS449 and DYF387S1) are characterized as “rapidly mutating”, and can differentiate between unrelated individuals and possibly between male relatives.Allelic frequencies were estimated with Arlequin v. 3.5. Gene and Haplotype diversities were estimated according to Nei formula. The discrimination capacity was also calculated by dividing the number of different haplotypes by the total number of individuals in the sample. The fraction of unique haplotypes was determined as the percent proportion of unique haplotypes. In conclusion, the recently introduced Y-Filer Plus® system provides innovative discriminatory power for forensic application