Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-19T15:30:58Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE KAYNARA CECILIA NERY RABELO.pdf: 2652314 bytes, checksum: e260b3caf6e8bee65596000a545c79d1 (MD5) / Made available in DSpace on 2016-04-19T15:30:58Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) TESE KAYNARA CECILIA NERY RABELO.pdf: 2652314 bytes, checksum: e260b3caf6e8bee65596000a545c79d1 (MD5) Previous issue date: 2015-06-30 / Insetos e outros artrópodes quando em locais de crime podem servir como vestígio criminal. O advento da genética forense pode auxiliar na obtenção do DNA humano a partir destes insetos, podendo relacionar o suspeito a cena do crime. Desta forma, esta pesquisa objetivou a obtenção e a comparação do perfil genético humano extraído de mosquitos hematófagos com diferentes metodologias para a extração de DNA, analisando os seguintes fatores: variação temporal para obtenção dos perfis genéticos após a hematofagia; a obtenção e a comparação dos perfis de DNA humano do sangue proveniente do trato digestivo dos mosquitos hematófagos com as amostras referências (saliva) de voluntários; influência da amônia, ácido lático e tipo sanguíneo, além da temperatura corporal dos voluntários e a relação na atratividade dos mosquitos e consequente obtenção do material genético; avaliou-se também a mistura de perfis genéticos provenientes de um único mosquito e o intervalo temporal após a hematofagia. Para a análise da comparação das extrações foi utilizado o kit DNA IQTM ,a resina Chelex® 100 e extração com NaOH; e para as outras variáveis em estudo utilizou-se somente o DNA IQTM. A quantificação foi realizada com o Quantifiler® Duo e a amplificação com o kit AMPFlSTR Identifiler® Plus® PCR, que analisou 15 loci STR e amelogenina. A quantificação para o estudo das misturas de DNA nos mosquitos foi realizada com PowerPlex 16HS System. Os dados foram analisados através do programa estatístico PATCAN v. 1.2 software e para a análise das misturas foi utilizado o programa DNA MIX v. 3.2 software. Os resultados demonstraram que o uso do DNA IQTM foi melhor quando comparado a resina Chelex® 100, com obtenção de perfis viáveis em até 72h após a refeição sanguínea. Não foi obtido perfil de DNA quando utilizado NaOH. Os resultados demonstraram também uma confrontação positiva entre o sangue encontrado no trato digestivo dos mosquitos e o material genético cedido pelos voluntários, como amostra referência. As análises bioquímicas demonstraram que o tipo sanguíneo com maior número de obtenção de perfil genético foi o tipo O; além disso, foi constatado valores de normalidade para o exame de lactato, mas para a análise de amônia foi obtido DNA também com valores maiores que o padrão de referência para este tipo de exame, tanto em homens quanto em mulheres. Houve obtenção de DNA nas temperaturas corporais registradas entre 36ºC a 37º C. Foi observado também que mistura de DNAs humano pode ser detectado a partir de um único mosquito hematófago. Desta forma, os resultados demonstraram que os mosquitos hematófagos quando encontrados em cenas de crimes tem efetivo valor forense. / Insects and others arthropods can be used as traces when located in the crime scene. The advent of forensic genetic can assist in obtaining human DNA from these insects, relating the suspect to the crime scene. So, this research aimed the obtainment and the comparison of the human gene profile extracted for the hematophagous mosquitoes with different methodologies to the DNA extraction, analyzing the following factors: temporal variation to the obtainment of the genetic profile after the hematophagy; obtainment and comparison of the human gene profile from the hematophagous mosquitoes´ digestive tract with the volunteers´ samples (saliva); influence of ammonia, lactic acid and blood type, besides the volunteers’ body temperature and the relation on mosquitoes´ attractiveness and genetic material obtainment; the compound of the genetic profile from one mosquito and temporal intermission after hematophagy was also evaluated. DNA IQTM, resin Chelex® 100 and extraction with NaOH was used to the analyses of the extract comparison. The quantification was held with Quantifiler® Duo and the amplification with AMPFlSTR Identifiler® Plus® PCR kit, that analyzed 15 loci STR and amelogenin. The quantification to study the compound of DNA in the mosquitoes was held with PowerPlex 16HS System. Data were analyzed through statistic program PATCAN v. 1.2 software and to analyze the profiles mixtures DNA MIX v. 3.2 software program was used. The results showed that the use of DNA IQTM was typical when compared with Chelex® 100, and success in gene amplification with obtainment of viable profiles up to 72 hours after blood meal. DNA profile was not obtained when used NaOH. The results also showed a positive confrontation between blood found in the mosquitoes´ digestive tract and the material assigned by the volunteers, with reference sample. Biochemical analysis demonstrated that the blood type with bigger obtainment number obtained profile gene was type O; besides that the human DNA profiles were achieved from hematophagous mosquitoes when compared with the correspondent biochemical analysis of the volunteer found normal values to lactate exam, but to ammonia analysis was obtained DNA with higher values than the reference standard to this type of exam, in both gender. There was DNA obtainment from body temperatures registered between 36°C to 37°C. It was also observed that human DNA compound can detected through a only single hematophagous mosquito. With that the results showed hematophagous mosquitoes when found in the crime scene have effective forensic value.

Despite the many advancements to forensic DNA analysis adopted by crime laboratories across the country, the most common method for the differential extraction of sexual assault samples has remained relatively unchanged since forensic deoxyribonucleic acid (DNA) typing was discovered in 1985. As the quantity and quality of extracted DNA has significant implications on the success of subsequent analysis methods, the development and optimization of effective extraction procedures is vital to progressing the field of forensic DNA analysis. The graduate students and faculty at the Boston University School of Medicine have been developing a differential extraction process that utilizes a multi-enzymatic approach to preferentially lyse and wash the cell types within temperature controlled environments. The overall procedure is less labor-intensive and time-consuming than the conventional method. Through the extraction process, the inhibitory nature of each enzyme on the amplification process is avoided, circumventing the need for an additional purification step. A single centrifugation step is required in order to pellet the sperm while the cumbersome wash steps are replaced with selective digestion in order to remove the residual epithelial cell DNA from the sperm fraction. The three enzyme used (EA1, Benzonase®, and Acrosolv) operate optimally at distinct temperatures which allows for controlled and sequential activation to achieve desired lysis and digestion outcomes. The enzymatic reactions are conducted within a DNA extraction lab thermal cycler to obtain rapid and accurate temperature changes. This novel temperature controlled differential extraction protocol has been developed and optimized for extraction of primarily liquid mixed samples in 0.2 milliliter (mL) tubes. The epithelial cell lysis and sperm cell lysis stages of the extraction contained a final reaction volume of 100 microliters (µL). Slight modifications to this 100 direct-lysis differential extraction method resulted in a similarly efficient method with a high male DNA yield (74-100%) and minimal female carryover among varying ratios of epithelial cells to sperm cells. This sensitive technique provided nearly complete profiles (14/16 loci) of the male contributor in mixed samples containing ~15,200 female epithelial cells and ~500 sperm, with complete profiles observed in mixed samples containing ~1000 sperm. This modified extraction protocol better accommodates sample sizes that may be encountered in forensic casework testing while providing a more concentrated sperm fraction, possibly eliminating the need for an additional concentration step in some dilute samples. The ease of implementation and the rapid processing time of 2-3 hours make it a great candidate for use in forensic DNA laboratories and may help alleviate backlogs of sexual assault kit. However, further work is needed to alter the composition of the sperm lysis buffer to make it compatible with currently used amplification kits. Until such time, caution must be taken in the kit selection used for amplification of extracts produced with this method. This study also demonstrated a sensitivity of the GlobalFiler® PCR Amplification Kit to inhibition by the buffers used in this extraction protocol, particularly the Orange+ Buffer. This inhibition has dramatic effects on the profile quality of the amplified sperm fractions, with extensive allelic drop-out observed even when the Orange+ Buffer concentration was scaled from 1.0X to 0.2X. Amplification using the AmpFℓSTR® Identifiler® Plus PCR Amplification Kit showed marginal recovery in the profile quality. Other expanded-loci STR amplification kits may also demonstrate resistance to this inhibition.

Differential extraction has proven to be a challenging and time-consuming process, often requiring up to six hours of a forensic analyst’s concentration. With the ever-increasing backlog of sexual assault evidence kits, the forensic community is using new ways to diminish this backlog, including more streamlined evidence processing and sample analysis. The goals for processing sexual assault samples include efficient recovery of sperm deoxyribose nucleic acid (DNA), simplified sample processing, and the development of a profile eligible for forensic analysis. Cost and time can also be limiting factors. The Cotton Research Lab at Boston University has developed a novel method of differential extraction that combines separation of epithelial and sperm cell fractions, nuclease treatment to reduce female DNA carryover and a direct-cell lysis protocol. With the exception of a single centrifugation step, the entire protocol is conducted using a thermalcycler in the DNA extraction laboratory. Thus, the process is a Temperature Controlled Differential Extraction (TCDE), and has been effectively adapted for use with liquid, dried, and aged samples. The purpose of this research is to explore methods which further adapt the protocol for best use with forensic casework samples, namely vaginal swabs. Sexual assault evidence collection kits may contain a variety of items, and commonly include cotton swabs for the collection of fluids from intimate sources. To simulate casework-type samples, swabs were prepared with liquid epithelial cell preparations and various semen dilutions (ranging from 1:1 to 1:1000). Amendments were made to the TCDE protocol for best DNA recovery from a swab, and buffer changes were made to enhance compatibility with polymerase chain reaction (PCR)-amplification kits widely utilized in forensic labs. Finally, post-coital swabs from female donors were analyzed using the TCDE protocol with modifications for forensic casework samples. Preliminary testing of casework-type swabs with protocol modifications showed high yields of DNA and successful separation of epithelial and spermatozoa fractions. The epithelial fraction, when yielding a mixed profile, demonstrated a clear major female contributor, and the spermatozoa fractions showed little to no female carryover, often exhibiting single source male profiles. The TCDE protocol with modifications for casework-type samples requires approximately 2 hours and 30 minutes of an analyst’s time, from the moment the swab is removed from its evidence packaging to an extraction ready for DNA quant and short tandem repeat (STR) amplification. The method provides increased DNA recovery, can be used with various amplification kits, and generate probative profiles and is time efficient. This robust and promising new method that has the potential to be automated and to contribute to the effort to reduce the backlog in the analysis of sexual assault evidence kits.

Forensic genotyping uses a multiplex short tandem repeat (STR) assay to amplify deoxyribonucleic acid (DNA) samples. One of the artifacts mostly commonly encountered in forensic DNA analysis is stutter, which are non-specific products from the polymerase chain reaction (PCR) that are typically one repeat unit shorter in length than the allelic amplicon. While stutter peaks are typically no taller than 10% of the parent peak on electropherograms, their peak heights can fall into similar ranges as minor contributor alleles in mixtures, creating a problem of how to distinguish artifacts from true allele peaks in these situations. One way to potentially address this issue is to find a PCR method that produces a much lower amount of stutter than the method currently used, which involves amplifying samples with commercial PCR kits designed for forensic applications. These kits all use some form of Taq DNA polymerase (derived from Thermus aquaticus). In an effort to examine whether the type of enzyme used in an assay affects the resulting stutter rates observed, the existing GlobalFiler™ PCR Amplification Kit (Applied Biosystems) protocol for forensic multiplex STR assays was modified to test different types of enzymes. This was done by amplifying the same DNA sample with GlobalFiler primers and different commercial proofreading enzymes and their accompanying reaction buffer using manufacturer-recommended PCR parameters. The DNA sample originated from a buccal swab that was extracted on the EZ1® Advanced (Qiagen). The DNA solution was quantified using the Quantifiler™ Duo DNA Quantification Kit (Applied Biosystems) on the 7500 Real-Time PCR System (Applied Biosystems). In order to first establish the validity of switching out enzymes in an established protocol, a DNA sample was amplified with the Type-it® Microsatellite Kit (Qiagen), another Taq-based kit that is also marketed for use in multiplex STR assays. After a complete profile was successfully generated, research proceeded with testing various high-fidelity DNA polymerases. Some of the enzymes tested were known to be Pyrococcus-like while others were fused to a DNA-binding domain to enhance processivity. Taq polymerases tend to produce products with 3’adenine-overhangs while proofreading enzymes produce blunt-ends. This change caused a one base pair difference in the resulting amplicon lengths, which was accommodated by manually assigning genotypes after results from fragment analysis by capillary electrophoresis using a 3130 Genetic Analyzer (Applied Biosystems) were interpreted by the GeneMapper™ software (Applied Biosystems). Additional amplification kits tested were: the UCP HiFidelity PCR Kit (Qiagen), Phusion™ Hot Start II High-Fidelity DNA Polymerase (Thermo Scientific), Platinum™ SuperFi™ II DNA Polymerase (Invitrogen), iProof™ High-Fidelity DNA Polymerase (Bio-Rad), Q5® High-Fidelity DNA Polymerase (New England Biolabs), and TruFi™ DNA Polymerase (Azura Genomics). Most of the kits produced profiles exhibiting a high degree of uneven amplification and varying levels of allelic dropout. In addition, all of the kits tested had much shorter peak heights compared to using GlobalFiler. Changing the type of enzyme used in an established protocol was found to be less straightforward than anticipated. Due to the poor quality results obtained in the first pass of trials, a few kits were selected to undergo optimization in the hopes of achieving higher quality results from which further analyses, such as comparing stutter rates, could be more reliably conducted. Both altered reagent amounts (higher enzyme concentration, higher DNA input mass) and different PCR parameters (decreased denaturation temperature, varying annealing temperature, decreased extension temperature, longer extension cycles, and longer final extension stage) were assessed. Only an increase in extension cycling time was found to produce better peak heights while maintaining balanced amplification of most of the targeted loci. Initial samples amplified with the Phusion enzyme exhibited multiple non-specific artifacts that were not stutter. Raising the annealing temperature for that enzyme’s protocol eliminated this issue. Therefore, higher annealing temperatures were pre-emptively used for several of the other enzymes tested. One of the explanations proposed for the uneven amplification observed is the presence of inhibitors in the commercial buffers used affecting downstream capillary electrophoresis. The Q5 High-Fidelity and TruFi DNA polymerases produced the best quality profiles; the UCP HiFidelity PCR Kit had the poorest results. Preliminary results indicated that none of the protocol alterations implemented significantly decreased stutter rates, nor was any one commercial enzyme found to have consistently lower stutter rates than the GlobalFiler kit. Due to the low number of trials carried out, the findings from this study require more replications with a wider variety of DNA polymerases to confirm that the type of enzyme used in an assay does not affect stutter rates.

A reliable and robust laboratory method is essential for the forensic analysis of deoxyribonucleic acid (DNA), particularly for low-template samples. Electropherogram peak heights are important to the identification of STR alleles, and these peak heights are prone to error. Since error can be introduced into the process during sample preparation, quantification, amplification, or analysis, validation studies are performed in an attempt to characterize the signal variation associated with the process. While current practices assess aspects of a method, such as sensitivity and reproducibility, the effects of daily laboratory alterations are often not considered. Additionally, samples used in a validation study may be prepared using serial dilutions. Therefore, understanding the extent to which error is propagated through the series and the effect it has on the results could help improve validation practices. This work aimed to assess the effect daily laboratory modifications have on the signal in a forensic electropherogram. Specifically, the variability in signal when different capillary and amplification kit lots were used was evaluated against the variability observed when a single sample was either injected or amplified multiple times. The variability was determined via the examination of peak heights, peak height ratios, stutter, and drop-out. The effect of serially diluting samples was examined via an in silico model of the dilution process, polymerase chain reaction (PCR), and capillary injection. The peak heights from simulated serially diluted samples using the concentration of a stock DNA were compared to the peak heights from simulated samples that were quantified after the dilution series was generated and prior to amplification. The different capillary lots and amplifications were found to result in greater variation compared to the multiple injections. Additionally, when the stutter percentages obtained from using multiple kit lots were compared to those obtained using the same kit lot, differences in stutter percentage deviations resulted in different stutter thresholds. Drop-out rates were also different between the samples amplified with one kit versus the same samples amplified with multiple kit lots. Therefore, at a minimum, multiple amplifications should be run on multiple capillary lots during validation. Further, if available, the use of multiple kit lots is recommended, particularly in cases where stutter thresholds or drop-out models are used during interpretation. Creating validation samples via serial dilutions was also found to increase the variation observed in peak height in the simulated samples, suggesting that samples should be quantified post-dilution. In addition to characterizing the variability of several components of DNA analysis, an alternative quantification method was investigated in order to decrease the overall variability associated with the quantification process. This work sought to develop an electrochemical biosensor using a single-stranded DNA (ssDNA) probe chemically adsorbed to a gold electrode. This would allow for the direct quantification of DNA and eliminate the need for qPCR and fluorescent-based oligonucleotide detection systems. The DNA probe was successfully adsorbed to the surface of the gold disk electrode, hybridized to a single-stranded complementary DNA sequence, and detected using square wave voltammetry. Additionally, the ability to control the amount of DNA chemisorbed to the electrode surface was investigated by varying the incubation time in the probe solution. The measured current increased as the incubation time increased from 15 minutes to one hour, after which it plateaued. The use of an electrochemical biosensor is a promising alternative to qPCR for the quantification of DNA, with one hour being the optimal incubation time in the probe solution.

The separation of sperm from female epithelial cells has been a topic of interest in forensic DNA (deoxyribonucleic acid) analysis since the origin of the field. One of the most needed applications of DNA analysis in the identification of the perpetrator of a sexual assault, as often there is little to no other evidence for identification. The largest hurdle to forensic DNA analysis in these cases is that vaginal or oral swabs from sexual assaults will have a mixture of the victim’s epithelial cells and the perpetrator’s sperm cells. It is well known that the analysis of complex mixtures can be difficult to impossible, especially when there is an added concern of low template DNA. Separating these cell types in the mixture evidence is the best way to avoid the need to deduce these difficult mixtures. Sperm and Epithelial Cells are morphologically different both in cell shape and DNA packaging. Nuclear DNA in epithelial cells are more loosely packaged around histones in a structure called a nucleosome. Sperm DNA is tightly packaged around protamines rather than histones. These DNA packaging differences can be utilized to preferentially lyse sperm and epithelial cells in order to separate them. Traditionally this is done by lysing epithelial cells with sodium dodecyl sulfate (SDS) and proteinase K (PK), separating this epithelial DNA from the sperm by centrifugations and finally lysis of the sperm using dithiothreitol (DTT) which reduces the disulfide bonds in the sperm DNA packaging. This method was developed by Peter Gill in 1985 and is still used by forensic laboratories to date. This differential extraction is very labor intensive and time consuming. This dual-enzyme differential extraction can be performed in roughly one hour, which is highly advantageous with the large amount of backlogged sexual assault cases that forensic laboratories have. This work was undertaken to improve the separation of epithelial DNA from sperm cells in the dual-enzyme differential extraction. Here we found that the DNA carryover into the sperm fraction was due to a combination of an inability to completely separate the non-sperm fraction liquid from the sperm pellet and the decreased efficiency of ZyGEM to fully lyse epithelial cells in clumps. The solution to this problem includes the addition of a wash of the sperm pellet after initial separation of the fractions. This wash step decreased the concentration of epithelial DNA to the point that its detection may only occur with very low concentrations of sperm DNA. / 2017-11-03T00:00:00Z

The determination and application of Analytical Threshold (AT) is a vital part of the forensic Deoxyribonucleic Acid (DNA) internal validation process. AT is the relative fluorescence unit (RFU) signal at which allelic peaks can be confidently distinguished from baseline noise. Several methods of calculating AT are currently being implemented within the forensic DNA community. These methods may utilize DNA negative sample data, DNA positive sample data, or both in their calculations. In this study, two of the DNA positive-based AT calculation techniques were chosen for assessment and comparison. The simplified upper limit approach (ULA) and the cost-based approach. ATs were calculated for each dye channel using a dilution series of 3 single source DNA samples ranging from 0.05-0.8ng. The ATs calculated via the cost-based approach consistently exhibited lower values than those determined via the ULA. As a result, the incidence of allelic drop-out exhibited by these AT values was also consistently lower, with an equivalent or only marginally increased incidence of baseline noise drop-in. These results indicated that the cost-based approach may be a more effective and practical method of calculating AT than the ULA, particularly in the analysis of low DNA template samples.

Em 2012, o Brasil aprovou a lei 12.654 que regulamenta o uso dos bancos de perfis genéticos para fins de investigação criminal. Esta lei é um dos marcos nas discussões acerca do uso do DNA nas investigações criminais que se intensificaram no país a partir de 2009 quando o FBI doou ao Brasil o Combined DNA Index System (CODIS). A chegada dos bancos de dados de DNA ao Brasil faz parte de um processo de expansão internacional de bancos nacionais de perfis genéticos. Esta tese trata do processo de introdução desta tecnologia no Brasil. Através de entrevistas com especialistas de diferentes áreas, tais como perícia criminal, direito e bioética, da observação e participação em seminários e congressos de perícia criminal e das discussões travadas em publicações de revistas científicas esta pesquisa busca uma compreensão etnográfica dos nexos entre ciência, direito, tecnologia, segurança e poder em torno do processo de introdução dos bancos de perfis genéticos no Brasil. Na primeira parte, a tese descreve algumas relações e significados que fizeram a identificação genética vir a ser sinônimo de precisão científica acerca da identificação humana e o deslizamento para sua aplicação nas investigações criminais. Na segunda parte, aborda os primeiros efeitos do processo de introdução da tecnologia de bancos de perfis genéticos no Brasil a partir do processo de elaboração da lei dos bancos de DNA, da emergência de novas trajetórias de peritos criminais em genética forense e de alguns desafios do cotidiano da coleta, análise e armazenamento dos vestígios da cena do crime. Conhecer e entender como são colocadas em prática as diversas mediações que envolvem a estabilização do banco de DNA para fins de investigação criminal no Brasil permite refletir como a relação entre tecnociência, direitos, cidadania e políticas de segurança implicam em opções técnicas, éticas e políticas. / In 2012, Brazil approved the Federal Law 12.654, which regulates the use of genetic profiles for criminal investigations. Such law is one of the main landmarks in discussions concerning the use of DNA in criminal investigations that have intensified across the country since 2009, when the FBI donated to Brazil the Combined DNA Index System (CODIS). The arrival of these databases in Brazil is part of an international expansion process of national genetic profiles databases. This dissertation is about the introduction process of such biotechnology in Brazil. Through interviews with specialists from different areas, such as forensic sciences, law and bioethics, from observation and participation in forensics seminars and congresses and from discussions set in scientific publications this research aims for an ethnographic understanding of the nexus between science, law, technology, security and power around the introductory process of the genetic profile databases in Brazil. In its first part, the dissertation describes some relations and meanings that made genetic identification become a synonym of scientific precision concerning human identification and the transition for its application in criminal investigation. In its second part, it approaches the first effects of the introductory process of the technology in Brazil through the DNA database’s law elaboration process, from the emergency of new trajectories of genetic forensic experts and from a few challenges of the daily collection, analysis and storage of evidences of the crime scene. To know and to understand the mediations involved in the stabilization of the DNA databases for criminal investigation allow us to reflect on how the relation between technoscience, law, citizenship and safety politics affects and engenders technical options, ethics and policies.

Since the mid 80, DNA fingerprinting has revolutionized forensic science, providing a powerful tool for research, currently being widely used in studies of paternity. Laboratories that work with forensic analysis of DNA carry increasing amounts of such studies and encourage the use of software systems that help with this type of analysis. One of the requirements for software of this magnitude is reliability, considering the level of detail of the study. Thus, it is interesting the use of formal methods. In this work, a software system called THÊMIS is built. THÊMIS uses Bayesian Networks as knowledge representation about studies of paternity, using inferences to obtain the results required by the forensic genetics regarding the calculation of the Index of Paternity (IP) / Fundação de Amparo a Pesquisa do Estado de Alagoas / Desde meados da década de 80, a tipagem do DNA (DNA fingerprinting) tem revolucionado a ciência forense, provendo uma poderosa ferramenta de investigação, sendo atualmente bastante utilizada em estudos de paternidade. Os laboratórios que trabalham com a análise forense de DNA realizam quantidades cada vez maiores de estudos desse tipo, incitando o uso de sistemas de software que auxiliem essa análise. Dentre as características essenciais para softwares dessa magnitude, está a confiabilidade, haja vista a minuciosidade do estudo. Dessa forma, é interessante o uso de métodos formais na execução de tais estudos. Neste trabalho, é construído um sistema de software, denominado THÊMIS, que utiliza o ferramental das Redes Bayesianas como meio de representação do conhecimento acerca de estudos de paternidade, obtendo por meio de inferências os resultados requeridos pela genética forense no que tange ao cálculo do Índice de Paternidade (IP)

Em 2012, o Brasil aprovou a lei 12.654 que regulamenta o uso dos bancos de perfis genéticos para fins de investigação criminal. Esta lei é um dos marcos nas discussões acerca do uso do DNA nas investigações criminais que se intensificaram no país a partir de 2009 quando o FBI doou ao Brasil o Combined DNA Index System (CODIS). A chegada dos bancos de dados de DNA ao Brasil faz parte de um processo de expansão internacional de bancos nacionais de perfis genéticos. Esta tese trata do processo de introdução desta tecnologia no Brasil. Através de entrevistas com especialistas de diferentes áreas, tais como perícia criminal, direito e bioética, da observação e participação em seminários e congressos de perícia criminal e das discussões travadas em publicações de revistas científicas esta pesquisa busca uma compreensão etnográfica dos nexos entre ciência, direito, tecnologia, segurança e poder em torno do processo de introdução dos bancos de perfis genéticos no Brasil. Na primeira parte, a tese descreve algumas relações e significados que fizeram a identificação genética vir a ser sinônimo de precisão científica acerca da identificação humana e o deslizamento para sua aplicação nas investigações criminais. Na segunda parte, aborda os primeiros efeitos do processo de introdução da tecnologia de bancos de perfis genéticos no Brasil a partir do processo de elaboração da lei dos bancos de DNA, da emergência de novas trajetórias de peritos criminais em genética forense e de alguns desafios do cotidiano da coleta, análise e armazenamento dos vestígios da cena do crime. Conhecer e entender como são colocadas em prática as diversas mediações que envolvem a estabilização do banco de DNA para fins de investigação criminal no Brasil permite refletir como a relação entre tecnociência, direitos, cidadania e políticas de segurança implicam em opções técnicas, éticas e políticas. / In 2012, Brazil approved the Federal Law 12.654, which regulates the use of genetic profiles for criminal investigations. Such law is one of the main landmarks in discussions concerning the use of DNA in criminal investigations that have intensified across the country since 2009, when the FBI donated to Brazil the Combined DNA Index System (CODIS). The arrival of these databases in Brazil is part of an international expansion process of national genetic profiles databases. This dissertation is about the introduction process of such biotechnology in Brazil. Through interviews with specialists from different areas, such as forensic sciences, law and bioethics, from observation and participation in forensics seminars and congresses and from discussions set in scientific publications this research aims for an ethnographic understanding of the nexus between science, law, technology, security and power around the introductory process of the genetic profile databases in Brazil. In its first part, the dissertation describes some relations and meanings that made genetic identification become a synonym of scientific precision concerning human identification and the transition for its application in criminal investigation. In its second part, it approaches the first effects of the introductory process of the technology in Brazil through the DNA database’s law elaboration process, from the emergency of new trajectories of genetic forensic experts and from a few challenges of the daily collection, analysis and storage of evidences of the crime scene. To know and to understand the mediations involved in the stabilization of the DNA databases for criminal investigation allow us to reflect on how the relation between technoscience, law, citizenship and safety politics affects and engenders technical options, ethics and policies.