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- Analysis of 17 STR data on 5362 southern Portuguese individuals-an update on reference databasePublication . Cabezas Silva, Raquel; Ribeiro, Teresa; Lucas, Isabel; Porto, Maria João; Costa Santos, Jorge; Dario, PauloThe 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.
- Got her mummy´s eyes: Eye color investigation using IrisPlex – preliminary studyPublication . Dario, Paulo; Rita Olivera, Ana; Ribeiro, Teresa; Lucas, Isabel; Marques, Manuela; Porto, Maria João; Costa Santos, Jorge; Corte Real, F.; Dias, DeodáliaSNP 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.
- Parâmetros populacionais e forenses da população do Sul de Portugal – atualização dos dados genéticos dos loci STR usados na casuística forensePublication . Silva, Raquel Cabezas; Ribeiro, Teresa; Lucas, Isabel; Porto, Maria João; Costa Santos, Jorge; Dario, Paulo
- Variabilidade da quantidade de ADN em zaragatoas bucais –estudo preliminarPublication . Lucas, Isabel; Oliveira, Rita; Dourado, Catarina; Dario, Paulo; Reis, R.; Vieira Da Silva, Cláudia; Amorim, António; Afonso Costa, Heloísa; Simão, F.; Ribeiro, Teresa; Porto, Maria João; Costa Santos, JorgeOs laboratórios de Genética Forense têm como objetivo a obtenção de perfis genéticos com vista à identificação humana, para a resolução de perícias do âmbito cível e criminal. Com vista à obtenção dos perfis genéticos dos indivíduos, é necessário efetuar colheitas de amostras biológicas dos mesmos, denominadas por amostras de referência. As mais comummente usadas são as obtidas por descamação do epitélio da mucosa bucal, com recurso ao uso de zaragatoas bucais. A variabilidade da quantidade de células colhidas através deste procedimento, pode ser originada por diversos fatores. O objetivo deste estudo é avaliar fatores que eventualmente possam contribuir para tal facto.
- Biological Evidences and Sexual Assault in Forensic MedicinePublication . Vieira, Claudia; Lucas, Isabel; Ribeiro, Teresa; Costa Santos, J.; Espinheira, RosaIntroduction Sexual assault crimes are ubiquitous; usually unwitnessed, so victim’s statements may be the only direct evidence that it has occurred. Medical examination and biological samples collection are of inequivocal importance. Presence of spermatozoa in smears, elevated acid phosphatase and the presence of Y-STR profiler in the victim’s evidence’s, could be crucial to corroborate victim’s testimony. The Y chromosome is far the most important scientific evidence, not only due to it’s gender specificity and easy amplification in a male/female mixtures, but also because it can easily contribute for the number of unrelated male contributor’s estimation in an biological evidence. The aim of this study is to ascertain a few characteristics concerning sexual harassment and a Y-haplotype profile obtention, which may help to prove or disprove a link between individuals and objects or places. Methodology Biological samples from 782 sexual assault cases were studied. Glass slide vaginal and anal smears were stained with Papanicolau’s and Harris Hematoxilin Solution. For the phosphatase test, a commercially available test paper strip was used (Phosphatesmo KM). DNA was extracted by phenol chloroform method and PCR amplification was performed with Powerplex® Y (Promega) or AmpF1STR Y-Filer (Applied Biosystems). Fragment analysis was done by capillary electrophoresis in an ABI 3130xl. Laboratory results were compared with other data such as, victim age, alleged assailant number, time between the act and collection of biological samples. Significant variables were entered in a logistic regression model using SPSS 17.0 for data analysis. Results and conclusion Descriptive analysis reveals that victim’s age varies between 1 to 90 years old, but almost 20% were under 12 years old. Almost 87% of cases had one perpetrator. Only 10% of the victim’s declared that they had consent sexual intercourse, in the previous 48 hours and 32% take a bath before the exam. Another variable studied was the mean time of 15 hours between the act and biological sample collection. Logistic regression demonstrates that the last two variables are of considerable importance in Y-profile obtention. Concerning acid phosphatase results a male genetic identification was obtained in 12,5 % of the negative cases. In conclusion, Y-STRs study, due to their sensitivity and specificity, should be used in every sexual assault cases, contributing to the final identification of perpetrator’s, and corroborating the victim’s story.
- Analysis of NGM STR loci in South Portuguese PopulationPublication . Ribeiro, Teresa; Dario, Paulo; Vital, Nádia; Sanches, Susana; Espinheira, Rosa; Geada, Helena; Costa Santos, JorgeAllele frequencies and other relevant forensic parameters of 15 loci studied with Applied Biosystems AmpFlSTRs NGM Kit were calculated in a population of individuals residing in the South of Portugal. Blood stain samples were obtained from a total of 350 unrelated individuals involved in paternity testing casework. This new kit has five loci not present in any other kit used in our laboratory (Promega Powerplex 16 System and Applied Biosystems Identifiler Plus): D10S1248, D22S1045, D2S441, D1S1656 and D12S391. The NGM multiplex kit is used in our forensic casework as an auxiliary screening tool to solve deficient casework such as fatherless paternity testing, and to help in paternity investigations with one genetic incompatibility after the routine seventeen loci typing. Furthermore, this five loci included in the European Standard Set are also recommended by the European Network of Forensic Science Institutes (ENFSI) and the European DNA Profiling group (EDNAP). These studies are necessary to calculate statistical forensic parameters such as power of discrimination, power of exclusion or minimum allele frequencies. Statistical parameters such as heterozigoty, homozigoty or allele frequencies were determined with Arlequim V3.5 and results compared with the ones reported in previous similar studies. As final remark, is important to remember that this kind of study is highly important for the Forensic Laboratories accreditation achievement
- O que dizem os teus olhos? Investigação de características fenotípicas em peça museológica e perspetiva de uso futuro em Genética ForensePublication . Dario, Paulo; Olivera, Ana Rita; Ribeiro, Teresa; Lucas, Isabel; Marques, Manuela; Porto, Maria João; Costa Santos, Jorge; Dias, Deodália; Corte Real, F.Os marcadores fenotípicos, do tipo SNP, têm vindo a ser estudados por vários grupos a nível mundial, pelo que começam a ser conhecidos marcadores para características fenotípicas não só para a cor dos olhos, mas também para a cor do cabelo e pele, os quais podem fornecer um conjunto valioso de informação para a identificação do dador da amostra em estudo. Este tipo de informação poderá ser tanto mais relevante se o dador da amostra possuir características fenotípicas que o distingam da população na qual se encontra inserido. Neste trabalho, foi estudada uma amostra de uma peça museológica com interesse histórico-científico que exemplifica como este tipo de novas metodologias poderá ter interesse em áreas como a investigação criminal ou como a antropologia física.