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Forensic DNA phenotyping and massive parallel sequencingBreslin, Krystal 04 December 2017 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In the forensic science community, there is an immense need for tools to help assist investigations where conventional DNA profiling methods have been non-informative. Forensic DNA Phenotyping (FDP) aims to bridge that gap and aid investigations by providing physical appearance information when other investigative methods have been exhausted. To create a “biological eye witness”, it becomes necessary to constantly improve these methods in order to develop a complete and accurate image of the individual who left the sample. To add to our previous prediction systems IrisPlex and HIrisPlex, we have developed the HIrisPlex-S system for the all-in-one combined prediction of eye, hair, and skin color from DNA. The skin color prediction model uses 36 variants that were recently proposed for the accurate prediction of categorical skin color on a global scale, and the system is completed by the developmental validation of a 17-plex capillary electrophoresis (CE) genotyping assay that is run in conjunction with the HIrisPlex assay to generate these genotypes. The predicted skin color output includes Very Pale, Pale, Intermediate, Dark and Dark-to-Black categories in addition to categorical eye (Blue, Intermediate, and Brown) and hair (Black, Brown, Blond, and Red) color predictions. We demonstrate that the HIrisPlex-S assay performs in full agreement with guidelines from the Scientific Working Group on DNA Analysis Methods (SWGDAM), achieving high sensitivity levels with a minimum 63pg DNA input. In addition to adding skin color to complete the pigmentation prediction system termed HIrisPlex-S, we successfully designed a Massively Parallel Sequencing (MPS) assay to complement the system and bring Next Generation Sequencing (NGS) to the forefront of forensic DNA analyses methods. Using Illumina’s MiSeq system enables the generation of HIrisPlex-S’s 41 variants using sequencing data that has the capacity to
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better deconvolute mixtures and perform with even more sensitivity and accuracy. This transition opens the door for a plethora of new ways in which this physical appearance assay can grow as sequencing technology is not limited by variant number; therefore, in essence many more traits have the potential to be included in this one assay design. For now, the HIrisPlex-S design of 41 variants using MPS is being fully assessed according to SWGDAM validated guidelines; therefore, this design paves the way for Forensic DNA Phenotyping to be used in any forensic laboratory. This new and improved HIrisPlex-S system will have a profound impact on casework, missing persons cases, and anthropological cases, as it is relatively inexpensive to run, HIrisPlex-S is easy to use, developmentally validated and one of the largest systems freely available online for physical appearance prediction from DNA using the freely available online web tool found at https://hirisplex.erasmusmc.nl/. Lastly, moving forward in our aim to include additional traits for prediction from DNA, we contributed to a large-scale research collaboration to unearth variants associated with hair morphology. 1026 samples were successfully sequenced using an inhouse MPS design at 91 proposed hair morphological loci. From this reaction, we were able to contribute to the identification of significant correlations between the SNPs rs2219783, rs310642 and rs80293268 with categorical hair morphology: straight, wavy or curly.
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Optimization of Marker Sets and Tools for Phenotype, Ancestry, and Identity using Genetics and ProteomicsWills, Bailey 08 1900 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / In the forensic science community, there is a vast need for tools to help assist investigations when standard DNA profiling methods are uninformative. Methods such as Forensic DNA Phenotyping (FDP) and proteomics aims to help this problem and provide aid in investigations when other methods have been exhausted. FDP is useful by providing physical appearance information, while proteomics allows for the examination of difficult samples, such as hair, to infer human identity and ancestry. To create a “biological eye witness” or develop informative probability of identity match statistics through proteomically inferred genetic profiles, it is necessary to constantly strive to improve these methods.
Currently, two developmentally validated FDP prediction assays, ‘HIrisPlex’ and ‘HIrisplex-S’, are used on the capillary electrophoresis to develop a phenotypic prediction for eye, hair, and skin color based on 41 variants. Although highly useful, these assays are limited in their ability when used on the CE due to a 25 variant per assay cap. To overcome these limitations and expand the capacities of FDP, we successfully designed and validated a massive parallel sequencing (MPS) assay for use on both the ThermoFisher Scientific Ion Torrent and Illumina MiSeq systems that incorporates all HIrisPlex-S variants into one sensitive assay. With the migration of this assay to an MPS platform, we were able to create a semi-automated pipeline to extract SNP-specific sequencing data that can then be easily uploaded to the freely accessible online phenotypic prediction tool (found at https://hirisplex.erasmusmc.nl) and a mixture deconvolution tool with built-in read count thresholds. Based on sequencing reads counts, this tool can be used to assist in the separation of difficult two-person mixture samples and outline the confidence in each genotype call.
In addition to FDP, proteomic methods, specifically in hair protein analysis, opens doors and possibilities for forensic investigations when standard DNA profiling methods come up short. Here, we analyzed 233 genetically variant peptides (GVPs) within hair-associated proteins and genes for 66 individuals. We assessed the proteomic methods ability to accurately infer and detect genotypes at each of the 233 SNPs and generated statistics for the probability of identity (PID). Of these markers, 32 passed all quality control and population genetics criteria and displayed an average PID of 3.58 x 10-4. A population genetics assessment was also conducted to identify any SNP that could be used to infer ancestry and/or identity. Providing this information is valuable for the future use of this set of markers for human identification in forensic science settings.
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Tagging systems for sequencing large cohortsNeiman, Mårten January 2010 (has links)
<p>Advances in sequencing technologies constantly improves the throughput andaccuracy of sequencing instruments. Together with this development comes newdemands and opportunities to fully take advantage of the massive amounts of dataproduced within a sequence run. One way of doing this is by analyzing a large set ofsamples in parallel by pooling them together prior to sequencing and associating thereads to the corresponding samples using DNA sequence tags. Amplicon sequencingis a common application for this technique, enabling ultra deep sequencing andidentification of rare allelic variants. However, a common problem for ampliconsequencing projects is formation of unspecific PCR products and primer dimersoccupying large portions of the data sets.</p><p>This thesis is based on two papers exploring these new kinds of possibilities andissues. In the first paper, a method for including thousands of samples in the samesequencing run without dramatically increasing the cost or sample handlingcomplexity is presented. The second paper presents how the amount of high qualitydata from an amplicon sequencing run can be maximized.</p><p>The findings from the first paper shows that a two-tagging system, where the first tagis introduced by PCR and the second tag is introduced by ligation, can be used foreffectively sequence a cohort of 3500 samples using the 454 GS FLX Titaniumchemistry. The tagging procedure allows for simple and easy scalable samplehandling during sequence library preparation. The first PCR introduced tags, that arepresent in both ends of the fragments, enables detection of chimeric formation andhence, avoiding false typing in the data set.</p><p>In the second paper, a FACS-machine is used to sort and enrich target DNA covered emPCR beads. This is facilitated by tagging quality beads using hybridization of afluorescently labeled target specific DNA probe prior to sorting. The system wasevaluated by sequencing two amplicon libraries, one FACS sorted and one standardenriched, on the 454 showing a three-fold increase of quality data obtained.</p> / QC20100907
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Tagging systems for sequencing large cohortsNeiman, Mårten January 2010 (has links)
Advances in sequencing technologies constantly improves the throughput andaccuracy of sequencing instruments. Together with this development comes newdemands and opportunities to fully take advantage of the massive amounts of dataproduced within a sequence run. One way of doing this is by analyzing a large set ofsamples in parallel by pooling them together prior to sequencing and associating thereads to the corresponding samples using DNA sequence tags. Amplicon sequencingis a common application for this technique, enabling ultra deep sequencing andidentification of rare allelic variants. However, a common problem for ampliconsequencing projects is formation of unspecific PCR products and primer dimersoccupying large portions of the data sets. This thesis is based on two papers exploring these new kinds of possibilities andissues. In the first paper, a method for including thousands of samples in the samesequencing run without dramatically increasing the cost or sample handlingcomplexity is presented. The second paper presents how the amount of high qualitydata from an amplicon sequencing run can be maximized. The findings from the first paper shows that a two-tagging system, where the first tagis introduced by PCR and the second tag is introduced by ligation, can be used foreffectively sequence a cohort of 3500 samples using the 454 GS FLX Titaniumchemistry. The tagging procedure allows for simple and easy scalable samplehandling during sequence library preparation. The first PCR introduced tags, that arepresent in both ends of the fragments, enables detection of chimeric formation andhence, avoiding false typing in the data set. In the second paper, a FACS-machine is used to sort and enrich target DNA covered emPCR beads. This is facilitated by tagging quality beads using hybridization of afluorescently labeled target specific DNA probe prior to sorting. The system wasevaluated by sequencing two amplicon libraries, one FACS sorted and one standardenriched, on the 454 showing a three-fold increase of quality data obtained. / QC20100907
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Využití metody paralelního sekvenování při stanovování zešikmení X inaktivace / Use of massive parallel sequencing in determination of skewed X inactivationVeselková, Tereza January 2016 (has links)
Skewed X chromosome inactivation has been often studied as a possible factor that influences manifestation of X-linked diseases in heterozygous women. Yet the association between phenotype and degree of skewing stays unclear for most disorders. Current works rely mostly on methods that are based on methyl-sensitive restriction while determining the X inactivation pattern and mainly the HUMARA assay which investigates the methylation profile in the AR gene. However those methods have some known disadvantages and therefore we are still seeking new methodical approaches. We used DNA isolated from whole blood and in some cases also buccal swabs to asses X inactivation patterns in 54 women using methylation-based methods for loci AR, CNKSR2 and RP2. Transcription-based assay was utilized to evaluate skewing of X inactivation in 32 of those women, whose samples were available for RNA extraction, using massive parallel sequencing and polymorphisms LAMP2 c.156A>T, IDS c.438C>T and ABCD1 c.1548G>A. Partly thanks to almost no stuttering during PCR the RP2 locus was the most informative in our study (71 % of women) and approximately the same number of women (69 %) were informative for the HUMARA assay. However when comparing the results of those two methods we determined difference greater than 10 % in...
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Co-infecção Plasmodium falciparum e Schistosoma haematobium: papel dos genes HLA não-clássicos de classe I (HLA-G, -E e -F) na suscetibilidade à malária / Plasmodium falciparum and Schistosoma haematobium co-infection: role of non-classical HLA class I genes (HLA-G, -E and -F) in susceptibility to malariaPaulin Sonon 31 October 2018 (has links)
A malária causada pelo Plasmodium falciparum (P. falciparum) e a bilharzíase urogenital causada pelo Schistosoma haematobium (S. haematobium) constituem duas doenças infecciosas tropicais alarmantes, sendo ambas endêmicas no Benin. Considerando que a malária (Th1) e a esquistossomose (Th2) apresentem perfis de citocinas divergentes, na presença de co-infecção, o S. haematobium poderia modular as respostas especificamente dirigidas contra o P. falciparum. Uma vez que, os genes que codificam as moléculas nãoclássicas de histocompatibilidade (HLA-G/-E/-F) possuam propriedades imunomoduladoras, pouca atenção tem sido dedicada ao estudo desses genes em populações da África Subsaariana, que são as de maior diversidade genética. O objetivo deste estudo foi avaliar a variabilidade dos genes HLA-G/-E/-F na população Toffin do Benin, e identificar fatores genéticos de suscetibilidade/resistência à malária causada pelo P. falciparum e/ou bilharziose urogenital, usando uma coorte de crianças (de 4 a 8 anos de idade) não aparentadas. Foram avaliados os segmentos codificantes e reguladores, englobando aproximadamente 5.1 kb do HLA-G, 7.7 kb do HLA-E e 6.2 kb do HLA-F, usando sequenciamento da nova geração. As frequências alélicas e haplotípicas do HLA-G/-E/-F, a diversidade genética, a diversidade nucleotídica, o equilíbrio de Hardy-Weinberg (HW) e de Tajima\'s D foram realizados utilizando o software ARLEQUIN v3.5.2. O desequilíbrio de ligação (LD) entre sítios variáveis com frequência alélica mínima (MAF) acima de 1% foi avaliado calculando o coeficiente de correlação r2 e os gráficos de LD foram visualizados usando o software Haploview 4.2. O estudo de associação foi implementada nos softwares PLINK v1.90b4.6 e R v3.4.2, usando modelos de regressão linear ou logística múltipla. 96, 37 e 68 sítios variáveis foram detectados ao longo de HLA-G/-E- F, respectivamente. Foram identificados 16, 19 e 15 haplótipos da promotora, 19, 15 e 29 haplótipos da codificadora, 12, 7 e 2 haplótipos da região 3\' não traduzida (3\'UTR), respectivamente, e ainda, 33 , 31 e 32 haplótipos estendidos, respectivamente. Todos os haplótipos promotores/codificadores/3\'UTR respeitaram os padrões já descritos na população mundial. O HLA-E foi o mais conservado, exibindo principalmente duas proteinas (E*01:01 e E*01:03), seguido do HLA-F, três proteínas (F*01:01, F*01:02 e F*01:03) e HLA-G, quatro proteínas: três normais (G*01:01, G*01:03 eSONON, P. Resumo xi G*01:04) e uma truncada (G*01:05N). Embora os alelos do HLA-G-E/-F observados na população Toffin tenham sido os mais frequentemente observados em vários países do mundo, as frequências dos haplótipos da região codificadora foram semelhantes às descritas para outras populações africanas (Guiné-Conakry e Burkina-Faso), quando comparadas com os países não-Africanos (Brasileiros), indicando que as variações ao longo desses genes estavam presentes nos Africanos antes da dispersão humana. Foram analisados 105 polimorfismos (MAF> 5%, valor P de HW> 0.05 e qualidade de genótipos> 97%) e 56 haplótipos com frequência mínima de 5%. Consideramos significativos, apenas os resultados exibindo valores de P <0.01 para polimorfismos e valores de P <0.01 antes da correção e valores de P <0.05 após correção de Bonferroni, para haplótipos. Encontramos as seguintes associações: i) o alelo inserção de 14 pares de bases do HLA-G (14 pb Ins) (em modelo dominante) foi associado ao risco de ocorrência de infecção por P. falciparum (infecções totais como infecções sintomáticas) e ao número de episódios de infecção (número elevado de episódios de infecções totais como de infecções sintomáticas), ii) polimorfismos HLA-G (- 1155 A e +755 A, em completo LD) (em modelo recessivo), e iii) haplótipo E.01.03.05- compatível em sinergia com o alelo -1988 C do HLA-E (em modelo aditivo) foram associados à proteção contra malária (em níveis de infecção como de densidade parasitária), e iv) o haplótipo E.Promo.2 foi associado à protecção contra a co-infecção do P. falciparum em crianças infectadas por S. haematobium. Excetuando o 14 pb Ins, estudos funcionais adicionais são necessários para revelar o papel desses marcadores na expressão dos genes HLA-G, -E e -F, para entender melhor o mecanismo de associação com doenças. / Plasmodium falciparum (P. falciparum) malaria and the urogenital bilharziasis caused by Schistosoma haematobium (S. haematobium) infection constitute the two alarming tropical infectious diseases; and both are endemic in Benin. Considering that malaria (Th1) and schistosomiasis (Th2) have divergent cytokine profiles, the presence of co-infection could modulate the responses specifically directed against P. falciparum. We hypothesize that the non-classical genes and molecules (HLA-G, -E and -F) of major histocompatibility complex (MHC) could be involved in this immunomodulation. Although these molecules have well known immunomodulatory properties, little attention has been devoted to the study of these non-classical class I HLA genes in sub-Saharan African populations. This study aimed to evaluate the diversity of HLA-G, -E and -F gene variable sites in the Beninese Toffin population, and to identify susceptibility/resistance genetic factors associated with P. falciparum malaria and/or urogenital bilharziasis in a Beninese cohort of unrelated schoolaged children (4 to 8 years old). We evaluated the complete gene variability (5.1 kb for HLAG, 7.7 kb for HLA-E and 6.2 kb for HLA-F) in the Beninese Toffin population using massive parallel sequencing. HLA-G, -E and -F allele and haplotype frequencies, gene diversity, average nucleotide diversity, Tajima\'s D and Hardy-Weinberg (HW) equilibrium were performed using ARLEQUIN v3.5.2 software. The linkage disequilibrium (LD) pattern among variable sites with a minimum allele frequency (MAF) above 1% was evaluated computing the correlation coefficient r2 and the LD plots were visualized using Haploview 4.2 software. The genetic association study was implemented on PLINK v1.90b4.6 and R v3.4.2 softwares using multiple logistic or linear regression models. Overall, 96, 37 and 68 variable sites were detected along the entire HLA-G, -E and -F, respectively, arranged into regionspecific haplotypes; i.e., promoter haplotypes (16, 19, and 15, respectively), coding haplotypes (19, 15, and 29, respectively), 3\' untranslated region (3\' UTR) haplotypes (12, 7 and 2, respectively) and extended haplotypes (33, 31 and 32, respectively). All promoter/coding/3\'UTR haplotypes followed the patterns already described in worldwide populations. Among the three genes, HLA-E was the most conserved, exhibiting mainly two full-length encoded-molecules (E*01:01 and E*01:03), followed by HLA-F (three full-lengthSONON, P. Abstract xiii proteins; F*01:01, F*01:02 and F*01:03) and HLA-G (four proteins; three full-length (G*01:01, G*01:03 and G*01:04) and one truncated (G*01:05N)). Although HLA-G/E/F alleles in the Toffin population were the most frequently observed worldwide, the frequencies of the coding haplotypes were closely similar to those described for other West African populations (Guinea-Conakry and Burkina-Faso) than for non-African ones (Brazilian population), indicating that variable sites along these genes were present in Africa before human dispersion. A total of 105 polymorphisms and 56 haplotypes were analyzed in the genetic association study to malaria and schistosomiasis susceptibility. Only results exhibiting respectively P-values < 0.01 and P-values < 0.05 (after Bonferroni correction) for polymorphisms and for haplotypes were considered as significant. The following associations were observed: i) HLA-G 14 base pairs (14bp) insertion was associated (under dominant model) with the risk of the occurrence of P. falciparum infection (all infections and symptomatic infections) and with high number of infection episodes (all infections and symptomatic infections), ii) HLA-G -1155 A and +755 A alleles (under recessive model) and iii) E.01.03.05-compatible haplotype in synergy with HLA-E -1988 C allele (under additive model) were associated with protection against P. falciparum (at infection as well as parasitic levels), and finally iv) the E.Promo.2 haplotype was associated with protection against malaria-schistosomiasis co-infection. The functional role of the genetic markers (alleles or haplotypes) associated with malaria and schistosomiasis suceptibility/resistance need to be investigated to better understand the mechanism that may explain these associations.
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Co-infecção Plasmodium falciparum e Schistosoma haematobium: papel dos genes HLA não-clássicos de classe I (HLA-G, -E e -F) na suscetibilidade à malária / Plasmodium falciparum and Schistosoma haematobium co-infection: role of non-classical HLA class I genes (HLA-G, -E and -F) in susceptibility to malariaSonon, Paulin 31 October 2018 (has links)
A malária causada pelo Plasmodium falciparum (P. falciparum) e a bilharzíase urogenital causada pelo Schistosoma haematobium (S. haematobium) constituem duas doenças infecciosas tropicais alarmantes, sendo ambas endêmicas no Benin. Considerando que a malária (Th1) e a esquistossomose (Th2) apresentem perfis de citocinas divergentes, na presença de co-infecção, o S. haematobium poderia modular as respostas especificamente dirigidas contra o P. falciparum. Uma vez que, os genes que codificam as moléculas nãoclássicas de histocompatibilidade (HLA-G/-E/-F) possuam propriedades imunomoduladoras, pouca atenção tem sido dedicada ao estudo desses genes em populações da África Subsaariana, que são as de maior diversidade genética. O objetivo deste estudo foi avaliar a variabilidade dos genes HLA-G/-E/-F na população Toffin do Benin, e identificar fatores genéticos de suscetibilidade/resistência à malária causada pelo P. falciparum e/ou bilharziose urogenital, usando uma coorte de crianças (de 4 a 8 anos de idade) não aparentadas. Foram avaliados os segmentos codificantes e reguladores, englobando aproximadamente 5.1 kb do HLA-G, 7.7 kb do HLA-E e 6.2 kb do HLA-F, usando sequenciamento da nova geração. As frequências alélicas e haplotípicas do HLA-G/-E/-F, a diversidade genética, a diversidade nucleotídica, o equilíbrio de Hardy-Weinberg (HW) e de Tajima\'s D foram realizados utilizando o software ARLEQUIN v3.5.2. O desequilíbrio de ligação (LD) entre sítios variáveis com frequência alélica mínima (MAF) acima de 1% foi avaliado calculando o coeficiente de correlação r2 e os gráficos de LD foram visualizados usando o software Haploview 4.2. O estudo de associação foi implementada nos softwares PLINK v1.90b4.6 e R v3.4.2, usando modelos de regressão linear ou logística múltipla. 96, 37 e 68 sítios variáveis foram detectados ao longo de HLA-G/-E- F, respectivamente. Foram identificados 16, 19 e 15 haplótipos da promotora, 19, 15 e 29 haplótipos da codificadora, 12, 7 e 2 haplótipos da região 3\' não traduzida (3\'UTR), respectivamente, e ainda, 33 , 31 e 32 haplótipos estendidos, respectivamente. Todos os haplótipos promotores/codificadores/3\'UTR respeitaram os padrões já descritos na população mundial. O HLA-E foi o mais conservado, exibindo principalmente duas proteinas (E*01:01 e E*01:03), seguido do HLA-F, três proteínas (F*01:01, F*01:02 e F*01:03) e HLA-G, quatro proteínas: três normais (G*01:01, G*01:03 eSONON, P. Resumo xi G*01:04) e uma truncada (G*01:05N). Embora os alelos do HLA-G-E/-F observados na população Toffin tenham sido os mais frequentemente observados em vários países do mundo, as frequências dos haplótipos da região codificadora foram semelhantes às descritas para outras populações africanas (Guiné-Conakry e Burkina-Faso), quando comparadas com os países não-Africanos (Brasileiros), indicando que as variações ao longo desses genes estavam presentes nos Africanos antes da dispersão humana. Foram analisados 105 polimorfismos (MAF> 5%, valor P de HW> 0.05 e qualidade de genótipos> 97%) e 56 haplótipos com frequência mínima de 5%. Consideramos significativos, apenas os resultados exibindo valores de P <0.01 para polimorfismos e valores de P <0.01 antes da correção e valores de P <0.05 após correção de Bonferroni, para haplótipos. Encontramos as seguintes associações: i) o alelo inserção de 14 pares de bases do HLA-G (14 pb Ins) (em modelo dominante) foi associado ao risco de ocorrência de infecção por P. falciparum (infecções totais como infecções sintomáticas) e ao número de episódios de infecção (número elevado de episódios de infecções totais como de infecções sintomáticas), ii) polimorfismos HLA-G (- 1155 A e +755 A, em completo LD) (em modelo recessivo), e iii) haplótipo E.01.03.05- compatível em sinergia com o alelo -1988 C do HLA-E (em modelo aditivo) foram associados à proteção contra malária (em níveis de infecção como de densidade parasitária), e iv) o haplótipo E.Promo.2 foi associado à protecção contra a co-infecção do P. falciparum em crianças infectadas por S. haematobium. Excetuando o 14 pb Ins, estudos funcionais adicionais são necessários para revelar o papel desses marcadores na expressão dos genes HLA-G, -E e -F, para entender melhor o mecanismo de associação com doenças. / Plasmodium falciparum (P. falciparum) malaria and the urogenital bilharziasis caused by Schistosoma haematobium (S. haematobium) infection constitute the two alarming tropical infectious diseases; and both are endemic in Benin. Considering that malaria (Th1) and schistosomiasis (Th2) have divergent cytokine profiles, the presence of co-infection could modulate the responses specifically directed against P. falciparum. We hypothesize that the non-classical genes and molecules (HLA-G, -E and -F) of major histocompatibility complex (MHC) could be involved in this immunomodulation. Although these molecules have well known immunomodulatory properties, little attention has been devoted to the study of these non-classical class I HLA genes in sub-Saharan African populations. This study aimed to evaluate the diversity of HLA-G, -E and -F gene variable sites in the Beninese Toffin population, and to identify susceptibility/resistance genetic factors associated with P. falciparum malaria and/or urogenital bilharziasis in a Beninese cohort of unrelated schoolaged children (4 to 8 years old). We evaluated the complete gene variability (5.1 kb for HLAG, 7.7 kb for HLA-E and 6.2 kb for HLA-F) in the Beninese Toffin population using massive parallel sequencing. HLA-G, -E and -F allele and haplotype frequencies, gene diversity, average nucleotide diversity, Tajima\'s D and Hardy-Weinberg (HW) equilibrium were performed using ARLEQUIN v3.5.2 software. The linkage disequilibrium (LD) pattern among variable sites with a minimum allele frequency (MAF) above 1% was evaluated computing the correlation coefficient r2 and the LD plots were visualized using Haploview 4.2 software. The genetic association study was implemented on PLINK v1.90b4.6 and R v3.4.2 softwares using multiple logistic or linear regression models. Overall, 96, 37 and 68 variable sites were detected along the entire HLA-G, -E and -F, respectively, arranged into regionspecific haplotypes; i.e., promoter haplotypes (16, 19, and 15, respectively), coding haplotypes (19, 15, and 29, respectively), 3\' untranslated region (3\' UTR) haplotypes (12, 7 and 2, respectively) and extended haplotypes (33, 31 and 32, respectively). All promoter/coding/3\'UTR haplotypes followed the patterns already described in worldwide populations. Among the three genes, HLA-E was the most conserved, exhibiting mainly two full-length encoded-molecules (E*01:01 and E*01:03), followed by HLA-F (three full-lengthSONON, P. Abstract xiii proteins; F*01:01, F*01:02 and F*01:03) and HLA-G (four proteins; three full-length (G*01:01, G*01:03 and G*01:04) and one truncated (G*01:05N)). Although HLA-G/E/F alleles in the Toffin population were the most frequently observed worldwide, the frequencies of the coding haplotypes were closely similar to those described for other West African populations (Guinea-Conakry and Burkina-Faso) than for non-African ones (Brazilian population), indicating that variable sites along these genes were present in Africa before human dispersion. A total of 105 polymorphisms and 56 haplotypes were analyzed in the genetic association study to malaria and schistosomiasis susceptibility. Only results exhibiting respectively P-values < 0.01 and P-values < 0.05 (after Bonferroni correction) for polymorphisms and for haplotypes were considered as significant. The following associations were observed: i) HLA-G 14 base pairs (14bp) insertion was associated (under dominant model) with the risk of the occurrence of P. falciparum infection (all infections and symptomatic infections) and with high number of infection episodes (all infections and symptomatic infections), ii) HLA-G -1155 A and +755 A alleles (under recessive model) and iii) E.01.03.05-compatible haplotype in synergy with HLA-E -1988 C allele (under additive model) were associated with protection against P. falciparum (at infection as well as parasitic levels), and finally iv) the E.Promo.2 haplotype was associated with protection against malaria-schistosomiasis co-infection. The functional role of the genetic markers (alleles or haplotypes) associated with malaria and schistosomiasis suceptibility/resistance need to be investigated to better understand the mechanism that may explain these associations.
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Desenvolvimento de marcadores de microssatélites e diversidade genética em acessos de Lippia alba (Mill.) N.E.Br. (Verbenaceae)Lopes, Juliana Mainenti Leal 03 March 2015 (has links)
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Previous issue date: 2015-03-03 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / CNPq - Conselho Nacional de Desenvolvimento Científico e Tecnológico / FAPEMIG - Fundação de Amparo à Pesquisa do Estado de Minas Gerais / Estudos recentes sugerem que a duplicação completa dos genomas é muito mais comum do que sua estabilidade, ocorrendo em todas as angiospermas. Nesse contexto, Lippia alba (Mill.) N.E.Br. (Verbenaceae) constitui um modelo interessante de estudo, pois além de ser a espécie mais estudada dentro do gênero Lippia, é amplamente utilizada na medicina popular apresentando importância econômica, sobretudo em função da riqueza de seus óleos essenciais. Estudos recentes demonstraram a existência de pelo menos cinco diferentes níveis de ploidia em Lippia alba, revelando grande plasticidade do genoma. A fim de contribuir para entender a variação genética e o processo de poliploidização em Lippia alba, o presente trabalho objetivou identificar novos marcadores genéticos do tipo microssatélite e estimar a diversidade genética em 100 acessos de Lippia alba. Foram avaliados nove loci já descritos e 16 novos marcadores. O tamanho dos fragmentos foi detectado por eletroforese capilar usando o sequenciador MegaBACE1000 (GE Healthcare, Buckinghamshire, UK). A identificação dos alelos foi inferida utilizando o software Fragment Profile (GE Healthcare, Buckinghamshire, UK). Os dados finais foram exportados para uma planilha do Excel® e foram transformados nos arquivos de entrada específicos para cada programa computacional. Os valores de PIC (polymorphism information content) e heterozigosidade foram calculados por meio do programa Cervus v3.0.7. Os coeficientes de similaridades de Jaccard e Dice foram calculados para construir um dendrograma de acordo com o algoritmo UPGMA (Unweighted Pair Group Method with Arithmetic Mean) por meio dos softwares NTSYS e PAST. Para a análise por inferência Bayesiana, foi utilizado o programa STRUCTURE v 2.3.4. Foi possível observar a formação de grupos de acordo com o nível de ploidia e inferir a possível origem de alguns citótipos baseada na similaridade genética entre os acessos. Os resultados contribuem para fortalecer a hipótese de que os acessos tenham surgido por autopoliploidia. / Recent studies suggest that complete genome duplication is much more common than its stability, occurring in almost all angiosperms. Lippia alba (Mill.) N.E.Br. (Verbenaceae), is the most studied species within the genus Lippia, and it is widely used in folk medicine presenting economic importance mainly due to the richness of their essential oils. Recent studies have demonstrated the existence of at least five different ploidy levels in Lippia alba revealing a large genome plasticity making the species an interesting model of study. To better understand the genetic variation and the polyploidization process in Lippia alba, this study aimed to identify new genetic microsatellite markers and estimate the genetic diversity for 100 Lippia alba accessions. We assessed 9 loci already described and 16 new markers. The size of the fragments was detected by capillary electrophoresis using MegaBACE1000 sequencer (GE Healthcare, Buckinghamshire, UK). The identification of alleles was inferred using the Fragment Profile software (GE Healthcare, Buckinghamshire, UK). Final data were exported to an Excel spreadsheet according to the input files of each software used. PIC values (polymorphism information content) and heterozygosity were calculated using Cervus v3.0.7 software. Jaccard and Dice similarity coefficient were calculated to construct a dendrogram according to UPGMA algorithm (Unweighted Pair Group Method with Arithmetic Mean) using NTSYS and PAST softwares. Bayesian inference analysis was performed using STRUCTURE v 2.3.4 program. It was possible to observe the formation of groups according to the ploidy level and infer the possible origin of some cytotypes based on genetic similarity among accessions. Results contribute to support the hypothesis that the cytotypes have emerged by autopolyploidy.
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Étiologies moléculaires des insuffisances surrénales primaires congénitales : développements statistiques pour la validation du séquençage parallèle massif / Genetics of congenital primary adrenal insufficiency and statistical developments for massive parallel sequencing validationBoulez, Florence 30 March 2018 (has links)
L'insuffisance surrénale primaire (ISP) se caractérise par un déficit en hormones stéroïdiennes lié à un trouble du cortex surrénal qui expose au risque d'insuffisance aiguë et de menace vitale. Actuellement, 80% des formes pédiatriques d'ISP sont d'origine génétique et 5% restent sans étiologie génétique identifiée. Les récentes découvertes de mutations de gènes du stress oxydant ouvrent le champ des recherches d'anomalies génétiques non spécifiques de la glande surrénale. Le séquençage parallèle massif (MPS) autorise aujourd'hui la réalisation de millions de séquences et l'étude simultanée de plusieurs gènes de plusieurs patients ce qui permet d'accélérer le diagnostic. C'est aussi la technique de choix pour la recherche de nouveaux gènes. Cependant, parmi les défis de cette nouvelle technologie, il est possible de citer la gestion de la très grande quantité de données qu'elle génère et le besoin d'une validation rigoureuse préalable à son utilisation à des fins diagnostiques.Le premier objectif du présent travail était d'établir un diagnostic génétique dans une cohorte de patients atteints d'ISP et de rechercher de nouveaux gènes. L'étude des génotypes et des phénotypes permet de comprendre les mécanismes physiopathologiques pour les engager dans le traitement et le conseil génétique.Le second objectif était le développement de méthodes bio-informatiques et d'inférence statistique pour faciliter le transfert du séquençage classique (Sanger) vers la technique MPS. Ce développement comprend l'analyse graphique de la qualité du séquençage, l'ajustement de modèles log-linéaires pour comparer les propriétés de différents « pipelines », et l'ajustement de modèles additifs généralisés pour estimer les contributions des sources d'erreurs de séquençage. Les analyses statistiques ont considéré chaque paire de bases comme unité statistique et chaque patient comme étude indépendante, ce qui confère à l'analyse simultanée de tous les patients le caractère d'une méta-analyse / Primary adrenal insufficiency (PAI) is characterized by an impaired production of steroid hormones due to an adrenal cortex defect. This condition exposes to the risk of acute insufficiency which may be life-threatening. Today, 80% of pediatric forms of PAI have a genetic origin but 5% have no clear genetic support. Recently discovered mutations in genes relative to the oxidative stress have opened the way to research works on genes unrelated to the adrenal gland. Massive Parallel Sequencing (MPS) is now able to perform millions of sequences and study simultaneously several genes in several patients, which accelerates the diagnosis. Above all, MPS is the preferred technique for new gene discoveries. However, among the challenges of this new technology one may cite the management of the huge amount of data MPS generates and the need for a strict validation process before the use of MPS for diagnosis purposes.The first objective of the present work was to establish a genetic diagnosis in a cohort of patients with PAI and search for new genes. Study the genotypes and phenotypes allows a better understanding of the physiopathological mechanisms of PAI and offering appropriate care for the patients and counseling for families. The second objective was the development of bioinformatic and statistical inference methods to help shifting from the classical Sanger sequencing to MPS. This shift involves a graphical analysis of the quality of sequencing, an adjustment of log-linear models to allow comparing the properties of different pipelines, an adjustment of the generalized additive models to allow estimating the contributions of various sources of sequencing errors. The statistical methods have considered each DNA base-pair as a statistical unit and each patient as a separate study which confers the simultaneous study of all patients the status of a meta-analysis
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Studium exprese mutantních alel a stavu X inaktivace ve vztahu ke klinickým projevům vybraných monogenních X vázaných onemocnění / Gene expression of mutant alleles and X inactivation pattern in patients with selected X-linked disordersČerná, Alena January 2019 (has links)
In comparison to men, the number of X-linked genes is doubled in women as they have two chromosomes X while men are hemizygotes for X-linked genes. This imbalance is compensated by X inactivation (XCI) process, also known as primary X-inactivation, occurring in the early stage of embryogenesis. X inactivation is a random process and females are mosaics of two cell populations. The ratio of expressed alleles in women can be random (50:50) or skewed (≥80:20). The skewed X inactivation may occur due to selection when one of the alleles is preferentially inactivated (secondary X inactivation). In this study XCI status in heterozygous females with various severity of phenotypic symptoms and traits in selected X linked inherited metabolic diseases is analysed, with the focus being Fabry disease - the deficiency of the enzyme alpha-galactosidase A encoded by GLA gene. Moreover, XCI in one family with X linked agammaglobulinemia is examined. Mutant alleles and XCI status based on various loci, different methodical approaches and different tissues is subjected to examination. For the first time, the direct analysis of GLA gene transcript to detect the allele ratio was used alongside with the single-nucleotide polymorphisms in the IDS and LAMP genes for allele-specific expression (ASE) and the AR, RP2 and...
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