L’étiologie des troubles du spectre autistique (TSA) est multifactorielle mettant en jeu une forte composante génétique ainsi que des facteurs environnementaux. A ce jour, il n’existe aucun biomarqueur facilitant un diagnostic précoce des TSA, ce qui permettrait une meilleure prise en charge des patients. De plus, les mécanismes physiopathologiques sont encore mal connus. La majorité des études sur les TSA ont été réalisées sur des populations occidentales. Ainsi, nous avons voulu étudier un groupe de patients libanais atteints de TSA. Nos objectifs s’articulent autour de trois volets : 1) L’identification de facteurs de risques environnementaux dans le but de mieux comprendre la pathologie. Les résultats de cette étude ont montré que plusieurs facteurs tels que la consanguinité, le stress au cours de la grossesse et la prématurité semblent être des facteurs de risques. 2) L’identification des variations structurales dans le génome des enfants atteints de TSA afin d'évaluer la contribution de CNV par l'approche de CGH array à haute résolution. Cette étude nous a permis d’identifier de nouveaux gènes dans les TSA ainsi de confirmer la présence des régions et des gènes déjà cités dans des études précédentes sur les TSA. 3) L’identification des métabolites urinaires et des voies métaboliques associés afin de proposer des biomarqueurs aidant à un diagnostic précoce et à une meilleure compréhension de la physiopathologie de la maladie. De nouveaux métabolites ont été identifiés, comme nous avons confirmé des variations anomalies déjà citées dans la littérature concernant certains métabolites qui pourraient représenter des marqueurs robustes de la maladie. / The etiology of autism spectrum disorders (ASD) is multifactorial involving a strong genetic component as well as environmental factors. To date, there is no biomarker facilitating early diagnosis of ASD to improve patient management and outcomes. In addition, the physiopathological mechanisms are still poorly understood. Most studies on ASD have been conducted in Western populations. Thus, we wanted to study a group of Lebanese patients with ASD. Our objectives focus around three aspects: 1) The identification of environmental risk factors in order to better understand the pathology. The results of this study showed that several factors such as consanguinity, stress during pregnancy and prematurity appear to be risk factors. 2) The identification of structural variations in the genome of children with ASD in order to evaluate the contribution of CNV by high resolution CGH array approach. This study allowed us to identify new genes in ASD as well as to confirm the presence of regions and genes already cited in previous ASD studies. 3) The identification of metabolites and associated metabolic pathways to provide biomarkers for early diagnosis and to better understanding of the pathophysiology of the disease. New metabolites have been identified and we have confirmed variations already mentioned in the literature concerning certain metabolites that could represent robust markers of the disease.

Deficiência intelectual é uma condição heterogênea e complexa, diagnosticada em 1-3% da população mundial. Desequilíbrios cromossômicos e variações no número de cópias (CNVs) são as causas mais frequentes de DI e, até recentemente, a maior parte desse desequilíbrio era averiguado por análises citogenéticas convencionais. Antes da utilização de microarrays cromossômicos (CMA), a causa etiológica da DI ainda permanecia desconhecida em ~60% dos pacientes. A aplicação de CMA tem revolucionado o diagnóstico da DI e de muitas outras doenças congênitas, permitindo explicar a etiologia molecular de parte da DI através da identificação de CNVs patogênicas. Nos países desenvolvidos, CMA é considerado como primeiro teste para avaliar pacientes com múltiplas anomalias congênitas, DI e/ou autismo. Contudo, nos países em desenvolvimento, a detecção de alterações ainda é feita principalmente por métodos citogenéticos convencionais. O objetivo desse estudo foi identificar, através do uso de SNP arrays, o espectro de anomalias cromossômicas presente em uma amostra de 40 pacientes com DI idiopática moderada e grave, apresentando ou não aspectos dismórficos e anomalias congênitas. Em especial, essa coorte de pacientes, em sua maioria (~2/3), não havia sido previamente cariotipada. Embora mundialmente desde 2010 a recomendação seja de realizar arrays antes de cariótipo, a maioria dos pacientes relatados em estudos já havia sido cariotipada antes de array ser oferecido a eles como teste. Foram identificadas alterações raras em 18 pacientes (45%). Em 12 (30%) desses Pacientes, as CNVs eram sabidamente patogênicas; esta taxa diagnóstica está muito acima da taxa de detecção reportada na literatura (~20%) e possíveis causas desta discrepância são discutidas. Outros 6 Pacientes (15%) apresentaram variantes raras de significado incerto (variants of unknown significance - VUS). Um aspecto adicional investigado foram os mecanismos envolvidos na formação de alguns dos rearranjos estruturais; enquanto nosso foco inicial era o uso de arrays para detecção de CNVs, se tornou evidente no decorrer do projeto que o padrão dos SNPs obtido nos arrays revelava, a partir do DNA, informação valiosa sobre a estrutura dos cromossomos e a composição heterogênea de células em uma amostra (mosaicismo). Esses resultados são discutidos em detalhes em duas situações: (1) A descrição de uma deleção terminal 1p36, associada a dissomia uniparental (UPD) em mosaico de segmentos de 1pter de diferentes tamanhos. Sugerimos que essa composição reflita eventos recorrentes de captura de telômero, embora processo similar nunca tenha sido descrito, e propomos um possível mecanismo responsável por originar esse desequilíbrio complexo. (2) Três dos nossos pacientes apresentam 4 cópias ou uma combinação de 3-4 cópias de segmentos proximais, na maior parte superpostos, de 15q11q13. Possíveis mecanismos de origem desses rearranjos são discutidos / Intellectual disability (ID) is a complex and heterogeneous condition affecting about 1-3% of the general population. Chromosomal imbalances and copy-number variations (CNVs) have been recognized as the most frequent causes of ID and, until recently, most of these imbalances were diagnosed by cytogenetic analysis. Before the application of microarray analysis (CMA), the underlying cause of ID remains unknown in ~60% of patients. The use of CMA has revolutionized the diagnosis of ID and several other congenital disorders, and have made it possible to identify pathogenic CNVs that could explain the molecular etiology of ID. In developed countries, CMA is considered the first-tier technique for the analysis of patients with multiple congenital anomalies, ID, and/or autism spectrum disorders. However, in developing nations, detection of alterations is still performed mainly by conventional cytogenetic techniques. The aim of this study was identifying, using a high-density resolution SNP microarray, chromosomal imbalances in a total of 40 patients presented with moderate-to-severe ID, associated or not with dysmorphic features and congenital anomalies. Particularly, most of the patients in the cohort (~2/3) was not karyotyped previously. Although CMA has been recommended as the first-tier test since 2010 all over the world, the majority of the patients in the reported studies were karyotyped before CMA was offered as a diagnostic test. Rare CNVs were detected in 18 patients (45%). Among those patients, 12 (30%) carried pathogenic CNVs. This yield is much higher than reported in the literature (~20%), and possible causes for this discrepancy are discussed. Six patients (15%) carried variant of unknown significance (VUS). Furthermore, mechanisms involved in structural rearrangements found in some patients were investigated. Even though the main focus of this dissertation was the detection of CNVs using high resolution SNP arrays, throughout the course of this project it was clear that the SNP patterns found could reveal crucial information about the structure of chromosomes and the heterogeneous composition of cells (mosaicism). Those results are discussed in detail in two situations: (1) One description of a terminal 1p36 deletion, associated with mosaic uniparental disomy (UPD) of different sized 1pter segments. We hypothesized that this composition reflects recurrent telomere capture events, although a similar process has never been described so far, and proposed a possible mechanism responsible for originating this complex imbalance. (2) Three of our patients carried four copies or a four-three copies-combination of a proximal, partially overlapping, 15q11q13 segment. Possible mechanisms responsible for this complex rearrangement are discussed

La vigne (Vitis vinifera) possède un métabolisme secondaire particulièrement riche donnant naissance à une large palette de molécules dont certaines sont impliquées dans les défenses contre les pathogènes et d'autres dans la grande diversité d’arômes qui fait la renommée des vins. L’analyse de la séquence de référence du génome de la vigne a permis de mettre en évidence une remarquable expansion de certaines familles de gènes liés au métabolisme secondaire par rapport aux autres plantes. Dans ce travail, j'ai étudié les familles gènes codant pour les cytochromes P450, dont certains sont impliqués dans la production d’arômes, les gènes codant pour les stilbènes synthases (STS), les endo-β-1,3-glucanases et les gènes de résistance de type NBS impliqués dans les défenses de la vigne. Ma thèse vise à proposer des hypothèses expliquant l’organisation structurale de ces familles de gènes et ainsi à mieux comprendre pourquoi certaines familles présentent une amplification dans le génome de la vigne. Des approches bioinformatiques ont été utilisées afin d’étudier ces différentes familles de gènes. Les gènes cytochromes P450 et gènes R de type NBS ont tout d'abord été annotés de manière manuelle dans le génome de référence de la vigne. L’expression des gènes endo-β-1,3- glucanases, STS et cytochromes P450 a été analysée en utilisant une approche transcriptomique à grande échelle. Pour ce faire, un outil a été développé durant cette thèse pour estimer le niveau d’expression des gènes à partir de données RNA-Seq disponibles dans les banques de données publiques. Parallèlement, des données de reséquençage d’ADN de 56 cépages et espèces de vigne ont été analysées, afin de déterminer les variations structurales de type CNV au sein des familles de gènes à domaine NBS et de gènes STS. Ces différents travaux ont permis de montrer que l’amplification des familles de gènes étudiées n’est pas spécifique du génome de référence mais est retrouvée dans l'ensemble du genre Vitis, mais également de mettre en évidence des variations structurales au sein des différents génomes étudiés. L'analyse de la famille STS a montré que ces gènes sont organisés en blocs de duplication, et que les gènes plus conservés sont aussi les plus exprimés. Nous avons également montré que les gènes à domaine NBS sont organisés en cluster, dont certains sont particulièrement soumis à variation. Ces travaux contribuent à une meilleure connaissance de facteurs de défense efficaces et durables ainsi que des gènes impliqués dans la synthèse d’arômes dans la vigne. Ces connaissances pourront bénéficier aux programmes de création variétale mis en œuvre à l’INRA de Colmar. / Grapevine (Vitis vinifera) has a particularly rich secondary metabolism, giving rise to a wide range of molecules, some of which are involved in defences against pathogens and others in the great diversity of aromas that make wines famous. Analysis of grapevine reference genome has shown a remarkable expansion of certain families of genes linked to secondary metabolism in comparison with the other plants. In this work, I have analysed gene families coding for cytochromes P450, some of them being involved in the production of aromas, genes coding for stilbene synthases (STS), endo-β-1,3-glucanases and NBS type resistance genes involved in grapevine defences. My thesis intends to propose hypothesis to explain the structural organisation of these families and therefore better understand why some of these families are amplified in the grapevine genome. Bioinformatic approaches have been used to study these different genes families. The cytochromes P450 and R genes of NBS type were manually annotated to improve the knowledge of these families of genes. The expression of endo-β-1,3-glucanases, STS and cytochromes P450 genes has been quantified using a large-scale transcriptomic approach. To this purpose, a tool has been developed during this thesis to estimate the level of genes expression from RNA- Seq data available in public databases. In the meantime, DNA resequencing data from 56 cultivars and grapevine species have been analysed to identify structural variations of CNV types within the genes with a NBS domain and the STS genes. These works showed that the amplification of the gene families of interest was not specific to the reference genome but occurred at the scale of the Vitis genus, but also to highlighted structural variations in different genomes. Regarding the STS genes, blocks of duplication and more conserved and expressed genes were identified. For the genes with NBS domain, a clustered organisation has been highlighted with some clusters varying more than others in the studied genotypes. These works contribute to a better knowledge of gene families for efficient and durable defence against pathogens and optimal aromas synthesis in grapevine. This knowledge will benefit to breeding programs currently in progress at INRA Colmar.

Submitted by admin tede (tede@pucgoias.edu.br) on 2018-06-19T18:06:59Z No. of bitstreams: 1 SAMARA SOCORRO SILVA PEREIRA.pdf: 764936 bytes, checksum: 434a8cd13e6701c05b6ea08edda95150 (MD5) / Made available in DSpace on 2018-06-19T18:06:59Z (GMT). No. of bitstreams: 1 SAMARA SOCORRO SILVA PEREIRA.pdf: 764936 bytes, checksum: 434a8cd13e6701c05b6ea08edda95150 (MD5) Previous issue date: 2018-03-14 / Copy Number Variation (CNV) has been associated with intelectual disability (ID) and this condition occur in approximately 2% of world population. Chromosomal Microarray Analysis (CMA) is being indicated as first-tier test for individuals with ID and has also helped to understand the mechanisms of CNV formation, classification of these rearrangements, type of recurrence, and its origin. The aim of this study was to infer the parental chromosome origin of de novo pathogenic CNV in patients with ID and their mechanisms of formation. Patients with clinical indications of ID were referred to Replicon Research Group/LaGene for G-band karyotyping. CMA approach was done for patients without numerical and/or structural rearrangements results in karyotype. After performing CMA and classification of CNVs, the parental origin of pathogenic CNVs was done using Mendelian error check based on SNPs markers available by ChAs software. In addition, the UCSC Genome Browser website was used to detect Low Copy Repeats (LCR) surrounding the CNVs to infer the mechanisms of their formation. In the period from 2013 to 2015 was performed G-band karyotyping in 290 patients with clinical indication of ID and a total of 193/290 (66.5%) were diagnosed by Karyotype. The group of patients who were not diagnosed using the karyotype, only 76/97 (78.3%) agreed to continue the investigation by CMA’s approach. After performing CMA, a total of 15 de novo pathogenic CNVs were observed, 10 CNV of loss and 5 CNV of gain, in 13/76 (17.1%) patients. The analysis of the parental origin showed 60% of CNVs are of maternal origin and 40% of paternal origin. It was not possible to detect the influence of parental age in the formation of CNVs. After analyzing the presence of surrounding LCRs, it was observed that 46.7% are recurrent CNVs and the mechanism of formation was Non- Allelic Homologous Recombination (NAHR), and 71.4% of these recurrent CNVs are of maternal origin. These data are in agreement with studies that affirm that the majority of CNVs of paternal origin are nonrecurrent due to germ cells replicate many times their genetic material in the pre-meiotic phase, being possible to infer the mechanism of formation of CNV that may have been by Microhomology-mediated break-induced replication (MMBIR) or Non-homologous end joining (NHEJ). / A variação no número de cópias (CNV) no genoma é um dos fatores etiológicos que pode desencadear a condição da deficiência intelectual (DI), sendo que esta condição atinge cerca de 2% da população mundial. A metodologia de análise cromossômica por microarranjo (CMA) além de ser indicada como teste de primeira escolha para pacientes com DI, tem ajudado também na compreensão da formação de CNVs e classificação destes rearranjos, quanto à patogenicidade, o tipo de recorrência e sua origem. E este estudo objetivou inferir a origem cromossômica parental das CNVs de novo patogênicas em pacientes com DI e seu mecanismo de formação. Os pacientes com indicação clínica de DI foram encaminhados ao Núcleo de Pesquisas Replicon/LaGene para realização do cariótipo com bandeamento GTG, e subsequentemente, os que não tiveram alteração numérica e/ou estrutural no cariótipo foram convidados a continuar a investigação em nível genômico, pela metodologia de CMA. Após realização do CMA e classificação das CNVs, foram realizadas a análise da origem parental das CNVs de novo patogênicas pela análise do erro mendeliano usando os marcadores de SNPs disponibilizado pelo software ChAS. Adicionalmente, foi usado o UCSC Genome Browser para detectar Repetições De Poucas Cópias (LCR) circundantes as CNVs para inferir o mecanismo de formação das mesmas. Foi realizado o cariótipo em 290 pacientes com indicação clínica de DI entre os anos de 2013 a 2015 e em 193/290 (66,5%) foram diagnosticados pelo cariótipo. Do conjunto de pacientes que não foram diagnosticados usando o cariótipo, apenas 76/97 (78,3%) aceitaram continuar a investigação pelo CMA. Após realizar o CMA, foi observado 15 CNVs de novo patogênicas, 10 CNVs de perda e 5 CNVs de ganho, em 13/76 (17,1%) pacientes. Na análise da origem parental, observou-se que 60% das CNVs são de origem materna e 40% de origem paterna. Não foi possível detectar a influência da idade parental na formação das CNVs. Ao analisar a presença de LCRs circundantes, observou-se que 46,7% das CNVs de novo patogênicas são recorrentes e o mecanismo de formação foi a Recombinação Homologa Não Alélica (NAHR), e 71,4% dessas CNVs recorrentes são de origem materna. Esses dados corroboram com os estudos que afirmam que a maioria das CNVs de origem paterna são não recorrentes devido às células germinativas replicarem inúmeras vezes o seu material genético na fase pré-meiótica, sendo possível inferir sobre o mecanismo de formação que pode ter sido por Replicação Induzida por Quebra e Mediada por Microhomologia (MMBIR) ou Junção de Extremidade Não Alélica (NHEJ).

Genome-wide association studies (GWAS) are a tool of high importance to associate genetic markers, genes and genomic regions with complex phenotypes and diseases, allowing to understand in details this regulation of gene expression as well as the genes, and then develop new techniques of diagnoses and treatment of diseases. Nowadays, the main genetic marker used in GWAS is the SNP (single nucleotide polymorphism), a variation that affects only one base of the DNA, being the most common type of variation between individuals and inside the genome. Even though there are multiple techniques available for GWAS, several complex traits still have unexplained heritability. To contribute to these studies, reference genetic maps are being created, such as the HapMap and 1000 Genomes, which have common genetic variants from world wide population (including European, Asian and African populations). In the last years, two solutions adopted to solve the missing heritability are to use different types of genetic variants and include the rare and population specific markers. Copy number variation (CNV) is a structural variant which use is increasing in GWAS in the last years. This variant is characterized for the deletion or duplication of a region a DNA and its length can be from few bases pair to the whole chromosome, as in Down syndrome. In collaboration of the Heart Institute (InCor-FMUSP), this work uses the dataset from Baependi Heart Study to establish a methodology to characterized the CNVs in the Brazilian population using SNP array data and associate them with height. This project uses the genetic and phenotype data of 1,120 related samples (family structure). For CNV calling, resources from the software PennCNV are used and methodologies of preprocessing, normalization, identification and other analysis are reviewed. The characterization of CNVs include information about location, size, frequency in our population and the patterns of inheritance in trios. The association of CNVs and height is made using linear mixed models and with information of family structure. The obtained results indicate that the Brazilian population has regions with variation in the number of copies that are not in the literature. General characteristics, such as length and frequency in samples, are similar to the information found in the literature. In addition, it was observed that the transmission of CNVs could not follow the Mendelian laws, since the frequency of trios which one parent has a deletion/duplication and the offspring is normal is higher than the frequency of trios with one parent and the offspring has a deletion/duplication. This work also identified a region on chromosome 9 that could be associated to height, being that carries of a duplication in this region can have the expected height dropped by approximately 3cm. / Estudos de associação genética (do inglês, Genome-wide association studies - GWAS) são uma ferramenta fundamental para associar marcadores genéticos, genes e regiões genômicas com doenças e fenótipos complexos, permitindo compreender em mais detalhes essa rede de regulação bem como mapear genes e, com isso, desenvolver técnicas de diagnóstico e tratamento. Atualmente, a principal variante genética utilizada nos estudos de associação é o SNP (do inglês, Single Nucleotide Polymorphism), uma variação que afeta apenas uma base do DNA, sendo o tipo de variação mais comum tanto entre os indivíduos como dentro do genoma. Apesar das diferentes técnicas disponíveis para os estudos de associação, muitas doenças e traços complexos ainda possuem parte de sua herdabilidade inexplicada. Para contribuir com estes estudos, foram criados banco de dados genéticos de referência, como o HapMap e o 1000 Genomes, que possuem representantes das variantes genéticas comuns das populações mundiais (européias, asiáticas e africanas). Nos últimos anos, duas das solucões adotadas para tentar explicar a herdabilidade de doenças e fenótipos complexos correspondem a utilizar diferentes tipos de variantes genéticas e incluir variantes raras e específicas para uma determinada população. O CNV (do inglês, Copy Number Variation) é uma variante estrutural que está ganhando espaço nos estudos de associação nos últimos anos. Essa variante é caracterizada pela deleção ou duplicação de uma região do DNA que pode ser de apenas alguns pares de bases até cromossomos inteiros, como no caso da síndrome de Down. Em parceria com o Instituto do Coração (InCor-FMUSP), este trabalho utiliza os dados do projeto Corações de Baependi para estabelecer uma metodologia para caracterizar os CNVs na população brasileira a partir de dados de SNPs e associá-los com a altura. O projeto inclui dados genéticos e fenótipos de 1,120 indivíduos relacionados (estruturados em famílias). Para a detecção dos CNVs, os recursos do software PennCNV são utilizados e metodologias de processamento, normalização, identificação e análises envolvidas são revisadas. A caracterização dos CNVs obtidos inclui informações de localização, tamanho e frequência na população e padrões de herança genética em trios. A associação dos CNVs com a altura é realizada a partir de modelos lineares mistos e utilizando informações sobre a estrutura de família. Os resultados obtidos indicaram que a população brasileira contém regiões (únicas) com variação no número de cópias que não estão identificadas na literatura. Características gerais dos CNVs, como tamanho e frequência no indivíduo, foram semelhantes ao que é apontado na literatura. Também foi observado que a transmissão de CNV pode não seguir as leis mendelianas, uma vez que a frequência de trios com um dos pais com deleção/duplicação e filho normal era superior à frequência dos trios com filho portador da mesma variação.

Deficiência intelectual é uma condição heterogênea e complexa, diagnosticada em 1-3% da população mundial. Desequilíbrios cromossômicos e variações no número de cópias (CNVs) são as causas mais frequentes de DI e, até recentemente, a maior parte desse desequilíbrio era averiguado por análises citogenéticas convencionais. Antes da utilização de microarrays cromossômicos (CMA), a causa etiológica da DI ainda permanecia desconhecida em ~60% dos pacientes. A aplicação de CMA tem revolucionado o diagnóstico da DI e de muitas outras doenças congênitas, permitindo explicar a etiologia molecular de parte da DI através da identificação de CNVs patogênicas. Nos países desenvolvidos, CMA é considerado como primeiro teste para avaliar pacientes com múltiplas anomalias congênitas, DI e/ou autismo. Contudo, nos países em desenvolvimento, a detecção de alterações ainda é feita principalmente por métodos citogenéticos convencionais. O objetivo desse estudo foi identificar, através do uso de SNP arrays, o espectro de anomalias cromossômicas presente em uma amostra de 40 pacientes com DI idiopática moderada e grave, apresentando ou não aspectos dismórficos e anomalias congênitas. Em especial, essa coorte de pacientes, em sua maioria (~2/3), não havia sido previamente cariotipada. Embora mundialmente desde 2010 a recomendação seja de realizar arrays antes de cariótipo, a maioria dos pacientes relatados em estudos já havia sido cariotipada antes de array ser oferecido a eles como teste. Foram identificadas alterações raras em 18 pacientes (45%). Em 12 (30%) desses Pacientes, as CNVs eram sabidamente patogênicas; esta taxa diagnóstica está muito acima da taxa de detecção reportada na literatura (~20%) e possíveis causas desta discrepância são discutidas. Outros 6 Pacientes (15%) apresentaram variantes raras de significado incerto (variants of unknown significance - VUS). Um aspecto adicional investigado foram os mecanismos envolvidos na formação de alguns dos rearranjos estruturais; enquanto nosso foco inicial era o uso de arrays para detecção de CNVs, se tornou evidente no decorrer do projeto que o padrão dos SNPs obtido nos arrays revelava, a partir do DNA, informação valiosa sobre a estrutura dos cromossomos e a composição heterogênea de células em uma amostra (mosaicismo). Esses resultados são discutidos em detalhes em duas situações: (1) A descrição de uma deleção terminal 1p36, associada a dissomia uniparental (UPD) em mosaico de segmentos de 1pter de diferentes tamanhos. Sugerimos que essa composição reflita eventos recorrentes de captura de telômero, embora processo similar nunca tenha sido descrito, e propomos um possível mecanismo responsável por originar esse desequilíbrio complexo. (2) Três dos nossos pacientes apresentam 4 cópias ou uma combinação de 3-4 cópias de segmentos proximais, na maior parte superpostos, de 15q11q13. Possíveis mecanismos de origem desses rearranjos são discutidos / Intellectual disability (ID) is a complex and heterogeneous condition affecting about 1-3% of the general population. Chromosomal imbalances and copy-number variations (CNVs) have been recognized as the most frequent causes of ID and, until recently, most of these imbalances were diagnosed by cytogenetic analysis. Before the application of microarray analysis (CMA), the underlying cause of ID remains unknown in ~60% of patients. The use of CMA has revolutionized the diagnosis of ID and several other congenital disorders, and have made it possible to identify pathogenic CNVs that could explain the molecular etiology of ID. In developed countries, CMA is considered the first-tier technique for the analysis of patients with multiple congenital anomalies, ID, and/or autism spectrum disorders. However, in developing nations, detection of alterations is still performed mainly by conventional cytogenetic techniques. The aim of this study was identifying, using a high-density resolution SNP microarray, chromosomal imbalances in a total of 40 patients presented with moderate-to-severe ID, associated or not with dysmorphic features and congenital anomalies. Particularly, most of the patients in the cohort (~2/3) was not karyotyped previously. Although CMA has been recommended as the first-tier test since 2010 all over the world, the majority of the patients in the reported studies were karyotyped before CMA was offered as a diagnostic test. Rare CNVs were detected in 18 patients (45%). Among those patients, 12 (30%) carried pathogenic CNVs. This yield is much higher than reported in the literature (~20%), and possible causes for this discrepancy are discussed. Six patients (15%) carried variant of unknown significance (VUS). Furthermore, mechanisms involved in structural rearrangements found in some patients were investigated. Even though the main focus of this dissertation was the detection of CNVs using high resolution SNP arrays, throughout the course of this project it was clear that the SNP patterns found could reveal crucial information about the structure of chromosomes and the heterogeneous composition of cells (mosaicism). Those results are discussed in detail in two situations: (1) One description of a terminal 1p36 deletion, associated with mosaic uniparental disomy (UPD) of different sized 1pter segments. We hypothesized that this composition reflects recurrent telomere capture events, although a similar process has never been described so far, and proposed a possible mechanism responsible for originating this complex imbalance. (2) Three of our patients carried four copies or a four-three copies-combination of a proximal, partially overlapping, 15q11q13 segment. Possible mechanisms responsible for this complex rearrangement are discussed

Les variations en nombre de copies (CNV) sont des gains ou pertes d’une séquence d’ADN et peuvent avoir un rôle dans la susceptibilité à certaines maladies. Les CNVs peuvent être détectés par les puces de SNPs de haute résolution en analysant les intensités des allèles avec des algorithmes de détection des CNVs tels que CNV partition, PennCNV et QuantiSNP. Dans cette thèse, nous avons évalué les performances de ces outils pour la détection des CNVs au niveau pangénomique et pour les tests d'association. Nous avons également étudié des stratégies d'association combinant les informations de l'allèle et du nombre de copies pour des SNP situés dans des CNV. Nous avons appliqué ces outils pour mener une étude d’association pan-génomique avec les CNV en utilisant les données de l'étude espagnole du cancer de lavessie (SBC)/EPICURO générées par la puce Illumina 1M.Nos résultats montrent une faible fiabilité et une faible sensibilité des algorithmes de détection des CNV. Dans la région du gène GSTM1 où un CNV très fréquent existe qui est associé au risque de cancer de la vessie, nous avons constaté que les algorithmes de détection des CNV ont de faibles performances. Néanmoins, l’utilisation de la mesure d'intensité des allèles dans les tests d'association peut alors être une alternative intéressante car cela nous a permis de détecter cette association connue. Pour les SNPs situés dans des CNVs, nous avons étudié plusieurs stratégies de tests d'association et nous avons montré que la plus puissante était d’utiliser un modèle avec deux termes correspondant respectivement à la somme et à la différence du nombre de copies des deux allèles. Finalement, en appliquant ces stratégies à l'étude (SBC)/EPICURO, nous avons identifié des CNVs potentiellement associés au risque de cancer de la vessie, ainsi que des SNP dont l'allèle et le nombre de copies pourraient être impliqués dans le risque de cancer de la vessie. / Copy number variations (CNVs) are losses or gains of DNA sequences that may play a role in specific disease susceptibility. CNVs can be detected by high-resolution SNP-arrays through the analysis of allele intensities with CNV calling algorithms such as CNVpartition, PennCNV and QuantiSNP. In this thesis, we identified and assessed the performances of available tools for CNV calling and for association testing, at the genome-wide level. We also investigatedassociation strategies that combine information on both the allele and the number of copies for SNPs located in CNV regions. We applied these tools to conduct a genome-wide association study with CNV using data from the Spanish Bladder Cancer (SBC)/EPICURO Study generated by the Illumina 1M SNP-array. Our results showed a low reliability and a low sensitivity of the investigated CNV calling algorithms applied to SNP-array data. The GSTM1 locus shows a very frequent CNV that is associated with bladder cancer (BC) risk. We reported that the calling algorithms performed very poorly in identifying this CNV. We proposed using allele intensity measures (LRR) as a screening step to assess association as it allowed the detection of the GSTM1 CNV association with BC. To combine the allele and the number of copies for SNPs located in CNV regions, we investigated several strategies of association testing and we showed that the more powerfulone used a two-term model with the sum and the difference of the number of copies of both alleles. Finally, by applying these strategies to the (SBC)/EPICURO Study, we identified CNV regions potentially associated with BC risk, as well as SNPs for which both the allele and the number of copies could be involved in BC risk.

MicroRNAs (miRNAs) are studied as key genetic elements that regulate the gene expression involved in different human diseases. Clinical sequence based variations like copy number variations (CNVs) affect miRNA biogenesis, dosage and target recognition that may represent potentially functional variants and relevant target bindings. To systematically analyze miRNA-related CNVs and their effects on related genes, a user-friendly free online database was developed to provide further analysis of co-localization of miRNA loci with human genome CNV regions. Further analysis pipelines such as miRNA-target to estimate the levels or locations of variations for genetic duplications, insertions or deletions were also offered. Such information could support the simulation of miRNA-target interactions.

Fibromyalgia (FM) is a highly disabling syndrome defined by a low pain threshold and a permanent state of pain. Widespread pain is accompanied by a constellation of symptoms such as fatigue, sleep disturbances and cognitive impairment, among others. The mechanisms explaining this chronic pain remain unclear. Nowadays, the most established/ plausible hypothesis underlying FM ethiopathogenesis is the existence of a dysfunction in pain processing, as supported by alterations in neuroimaging and neurotransmitters levels. The etiology of FM involves the interaction of environmental and genetic susceptibility factors. The genetic contribution to FM has been proven by the presence of a higher concordance of monozygotic than dizygotic twins as well as family aggregation. However, the individual genetic and environmental factors involved have not been identified. The aim of this thesis was to elucidate genetic susceptibility factors for fibromyalgia. We assessed this objective through three main approaches: the identification of FM clinically homogeneous subgroups with a two step cluster analyses, a genome-wide association study in order to evaluate the possible contribution of single nucleotide polymorphisms with Illumina 1 million duo array, and array comparative genomic hybridization experiments to identify regions varying in copy number that could be involved in FM susceptibility,using Agilent 2X400K platform. 48 variables were evaluated in 1,446 Spanish FM cases fulfilling 1990 ACR FM criteria. A partitioning analysis was performed to find groups of variables similar to each other. Variables clustered into three independent dimensions: “symptomatology”, “comorbidities” and “clinical scales”. Only the two first dimensions were considered for the construction of FM subgroups, classifying FM samples into three subgroups: low symptomatology and comorbidities (Cluster 1), high symptomatology and comorbidities (Cluster 2), and high symptomatology but low comorbidities (Cluster 3). These subgroups showed differences in measures of disease severity and were further implemented in genetic analysis. Genome-wide association study was performed in 300 FM cases and 203 controls. No SNP reached GWAS association threshold, but 21 of the most associated SNPs were chosen for replication in over 900 cases and 900 pain free-controls. Four of the strongest associated SNPs selected for replication showed a nominal association in the joint analysis. In particular, rs11127292 (MYT1L) was found to be associated to FM with low comorbidities. Array comparative genomic hybridization detected 5 differentially hybridized regions. They were followed up and one of these regions was validated though a multiplex PCR experiment. An intronic deletion in NRXN3 showed to be associated to female cases of FM and in particular those with low levels of comorbidities. Replication analysis showed a stronger association when considering only female cases and controls and low comorbidities. This enhance the importance of gender in FM etiopathogenesis and could be pointing to the existence of a different genetic background for FM in males and females highlights the importance of identifying FM homogeneous subgroups for the detection of FM genetic susceptibility factors. If the proposed FM candidate genes are further validated in replication studies, this would constitute a change in the FM ethiologycal concept, as several of these candidates are known neuropsychiatric disease associated genes (autism, addiction, mental disability). This would highlight a novel neurocognitive involvement in this disorder, currently considered musculoskeletal and affective. / La fibromialgia (FM) es una enfermedad de etiología desconocida que se caracteriza por dolor crónico generalizado, junto a una amplia constelación de síntomas acompañantes. La base etiopatogénica que explica este estado permanente de dolor es aún desconocida. Hasta la fecha la teoría más plausible es la existencia de una disfunción en la transmisión del dolor. Los estudios familiares han mostrado una considerable agregación familiar en FM,sugiriendo la importancia de los factores genéticos en el desarrollo de estos cuadros. Con la presente tesis se ha pretendido estudiar e identificar variantes del genoma (polimorfismos de base única (SNPs)- y variantes en el número de copia –CNVs) asociadas a FM, con el objetivo de profundizar en la etiología de la enfermedad. Para ello, se han llevado a cabo tres grandes aproximaciones: la identificación de subgrupos clínicos homogéneos de FM mediante un análisis de clusters, un estudio de genoma completo (GWAS) para el análisis directo de SNPs y experimentos de hibridación genómica comparada mediante arrays (aCGH) con el fin de identificar regiones variables en el número de copia asociadas a FM. El análisis de clusters ha permitido la identificación de tres subgrupos de FM en función de los niveles de sintomatología y de comorbilidad personal y familiar. Los resultados del GWAS indican una posible contribución del sistema nervioso central en el desarrollo de FM, ya que las enfermedades neurológicas aparecen como sobrerrepresentadas en el estudio de pathways realizado en los SNPs que presentaban mayor asociación, y un SNP en el gen MYT1L ha presentado asociación estadísticamente significativa con FM con niveles bajos de comorbilidad, poniendo de manifiesto la importancia de identificar subgrupos clínicamente homogéneos para la detección de factores de susceptibilidad genética para FM. Un CNV en el gen neurexina3 ha mostrado, asimismo, asociación en mujeres con FM, y en particular, en aquellas con bajos niveles de comorbilidad, siendo un nuevo argumento a favor de la implicación del SNC. La confirmación de las variantes detectadas en nuevas cohortes de fibromialgia supondría un giro conceptual de la enfermedad hacia una visión más neurocognitiva que osteomuscular.

cn.MOPS is a model-based algorithm used to quantitatively detect copy-number variations in next-generation, DNA-sequencing data. The algorithm is implemented as an R package and can speed up processing with multi-CPU parallelism. However, the maximum achievable speedup is limited by the overhead of multi-CPU parallelism, which increases with the number of CPU cores used. In this thesis, an alternative mechanism of process acceleration is proposed. Using one CPU core and a GPU device, the proposed solution, gcn.MOPS, achieved a speedup factor of 159× and decreased memory usage by more than half. This speedup was substantially higher than the maximum achievable speedup in cn.MOPS, which was ∼20×. / Graduate / 0984 / 0544 / 0715 / alkhamis@uvic.ca