<p>This thesis focuses on the identification of genetic factors underlying two inherited human phenotypes: hearing loss and monoamine oxidase activity. </p><p>Non-syndromic hearing loss segregating in a Swedish family was tested for linkage to 13 previously reported candidate loci for hearing disabilities. Linkage was found to two loci: DFNA12 (llq22-q24) and DFNA2 (lp32). A detailed analysis of the phenotypes and haplotypes shared by the affected individuals supported the hypothesis of digenic inheritance of hearing disability in the Swedish family. Mutation screening of α-tectorin, a gene residing within the DFNA12 region revealed a mutation of a conserved amino acid (Cys to Ser), that segregated with the disease. The identification of the mutation added support to the involvement of α-tectorin in hearing disabilities. In contrast, no mutations were identified in two candidate genes at the DFNA2 locus, that were reported to cause hearing loss in other families. It is possible that the DFNA2 locus contains a third, not yet identified, hearing loss gene. </p><p>Monoamine oxidase A (MAOA) and B (MAOB) catalyze the degradation of certain neurotransmitters in the central nervous system and are associated with specific behavioral and neuropsychiatric human traits. Activity levels of both monoamine oxidases (MAO) are highly variable among humans and are determined by unknown genetic factors. This study investigated the relationship of different MAO alleles with MAO mRNA levels and enzyme activity in human brain. Several novel DNA polymorphisms were identified in a group of Swedish individuals. Haplotypes containing several closely located MAOA polymorphisms were assessed in Asian, African, and Caucasian populations. The haplotype distribution and diversity pattern found among the three populations supported the occurrence of a bottleneck during the dispersion of modem humans from Africa. </p><p>Allelic association studies conducted on postmortem human brain samples, revealed the association between a SNP in the MAOB intron 13, and different levels of both MAO enzyme activities. This suggested that this SNP is in linkage disequilibrium with at least one novel functional DNA polymorphism that controls MAO enzyme activities in human brain. The identification of functional polymorphisms regulating the activity of these enzymes will help to elucidate the involvement of MAO in human behavior and neuropsychiatric conditions. </p>

This thesis focuses on the identification of genetic factors underlying two inherited human phenotypes: hearing loss and monoamine oxidase activity. Non-syndromic hearing loss segregating in a Swedish family was tested for linkage to 13 previously reported candidate loci for hearing disabilities. Linkage was found to two loci: DFNA12 (llq22-q24) and DFNA2 (lp32). A detailed analysis of the phenotypes and haplotypes shared by the affected individuals supported the hypothesis of digenic inheritance of hearing disability in the Swedish family. Mutation screening of α-tectorin, a gene residing within the DFNA12 region revealed a mutation of a conserved amino acid (Cys to Ser), that segregated with the disease. The identification of the mutation added support to the involvement of α-tectorin in hearing disabilities. In contrast, no mutations were identified in two candidate genes at the DFNA2 locus, that were reported to cause hearing loss in other families. It is possible that the DFNA2 locus contains a third, not yet identified, hearing loss gene. Monoamine oxidase A (MAOA) and B (MAOB) catalyze the degradation of certain neurotransmitters in the central nervous system and are associated with specific behavioral and neuropsychiatric human traits. Activity levels of both monoamine oxidases (MAO) are highly variable among humans and are determined by unknown genetic factors. This study investigated the relationship of different MAO alleles with MAO mRNA levels and enzyme activity in human brain. Several novel DNA polymorphisms were identified in a group of Swedish individuals. Haplotypes containing several closely located MAOA polymorphisms were assessed in Asian, African, and Caucasian populations. The haplotype distribution and diversity pattern found among the three populations supported the occurrence of a bottleneck during the dispersion of modem humans from Africa. Allelic association studies conducted on postmortem human brain samples, revealed the association between a SNP in the MAOB intron 13, and different levels of both MAO enzyme activities. This suggested that this SNP is in linkage disequilibrium with at least one novel functional DNA polymorphism that controls MAO enzyme activities in human brain. The identification of functional polymorphisms regulating the activity of these enzymes will help to elucidate the involvement of MAO in human behavior and neuropsychiatric conditions.

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No. of bitstreams: 2 license_rdf: 0 bytes, checksum: d41d8cd98f00b204e9800998ecf8427e (MD5) tese_ivy_bastos_ramis.pdf: 1360974 bytes, checksum: 5f055cbf4d5ce0a95672ccdf092907c8 (MD5) Previous issue date: 2014-11-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Helicobacter pylori é uma bactéria que infecta a mucosa gástrica de aproximadamente 50% da população humana mundial. A infecção por H. pylori tem sido associada a uma variedade de doenças, tais como gastrite, doença ulcerosa péptica e carcinoma gástrico. Acredita-se que a combinação de variáveis ambientais/comportamentais, fatores genéticos do hospedeiro e genes de patogenicidade bacteriana possa interferir na gravidade da lesão gástrica e no desfecho clínico de infecção por H. pylori. Desta forma, o presente trabalho objetivou determinar a frequência e potenciais fatores de risco da infecção por H. pylori, assim como identificar os polimorfismos nos genes da interleucina (IL)-1, IL-6, IL-8 e IL-10 e suas associações com infecção por H. pylori, com cytotoxin associated gene A (gene cagA) de H. pylori e com patologias gástricas. Para isso, foi conduzido um estudo transversal, incluindo amostras de biópsia gástrica de 227 pacientes, submetidos à endoscopia digestiva alta. Um questionário foi aplicado aos pacientes antes da endoscopia. O diagnóstico de H. pylori baseou-se na histologia e na polymerase chain reaction (PCR). O gene cagA foi identificado por PCR. Os polimorfismos nos genes da IL-1B (nas posições -511, -31 e +3954), IL-6 (na posição -174), IL-8 (na posição -251) e IL-10 (nas posições -819 e -592) foram detectados por PCR-restriction fragment length polymorphism (RFLP). A análise do polimorfismo variable number of tandem repeat (VNTR) no gene IL-1RN foi realizada por PCR, seguida por eletroforese em gel de agarose. Dos 227 pacientes incluídos neste estudo, 151 foram positivos para H. pylori e 76 negativos. Com base nos questionários aplicados aos pacientes, verificou-se existir associação significativa entre a presença de H. pylori e a aglomeração familiar, a idade, e os diagnósticos endoscópicos e histológicos. Quanto aos fatores genéticos do hospedeiro observou-se que os polimorfismos nas regiões promotoras dos genes IL-1B e IL-8 estavam significativamente relacionados à infecção por H. pylori. As cepas de pacientes H. pylori positivos portadores do gene cagA foram significativamente associadas com o polimorfismo da IL-1B na posição -511. Adicionalmente, na presença da infecção pelo H. pylori, demonstrou-se que os polimorfismos na região promotora do gene IL-1B estiveram correlacionados com um risco aumentado de gastrite, enquanto aqueles nos genes da IL-8 e da IL-10 foram associados a um risco elevado da doença ulcerosa péptica. Conclui-se que, provavelmente, os polimorfismos genéticos do hospedeiro exerçam influência sobre o curso e a gravidade das doenças gástricas. Espera-se que os resultados deste trabalho possam contribuir, em breve, tanto para a prevenção dessas desordens quanto para uma terapia mais adequada e eficiente, isto porque o conhecimento das bases moleculares do hospedeiro e do microrganismo viabiliza o desenvolvimento de testes moleculares, os quais poderão ser aplicados em prol de um correto prognóstico das patologias gástricas. / Helicobacter pylori is a bacterium that infects the gastric mucosa of approximately 50% of the world´s human population. H. pylori infection has been associated with a variety of diseases such as gastritis, peptic ulcer disease and gastric carcinoma. It is believed that the combination of environmental/behavioral variables, host genetic factors and bacterial pathogenicity genes can interfere in the severity of gastric damage and in the clinical outcome of H. pylori infection. In this sense, the present study aimed to determine the frequency and potential risk factors of the H. pylori infection, even as identify polymorphisms in the interleukin (IL)-1, IL-6, IL-8 and IL-10 genes and their associations with H. pylori infection, with cagA gene of H. pylori, and with gastric pathologies. For this, it was conducted a cross-sectional study, including gastric biopsy samples from 227 patients, submitted to upper gastrointestinal endoscopy. A questionnaire was applied to the patients before endoscopy. The diagnosis of H. pylori was based in histology and in polymerase chain reaction (PCR). The cagA gene was identified by PCR. The polymorphisms in the genes of IL-1B (at positions -511, -31 and +3954), IL-6 (at position -174), IL-8 (at position -251) and IL-10 (at positions -819 and -592) were detected by PCR-restriction fragment length polymorphism (PCR-RFLP). The analysis of the variable number of tandem repeat (VNTR) polymorphism in the IL-1RN gene was performed by PCR followed by electrophoresis agarose gel. Of the 227 patients included in this study, 151 were positive for H. pylori and 76 negative. Based on the questionnaires applied to the patients, it was found a significant association between the presence of H. pylori and the household crowding, the age, and the diagnoses histological and endoscopic. As for host genetic factors was observed that polymorphisms in the promoter region of the IL-1B and IL-8 genes were significantly related with H. pylori infection. The strains from patients H. pylori positive carrying the cagA gene were significantly associated with the polymorphism of IL-1B at position -511. Additionally, in the presence of H. pylori infection, it was demonstrated that polymorphisms in the promoter region of the IL-1B gene were correlated with an enhanced risk of gastritis, while those in the IL-8 and IL-10 genes were associated with higher risk of peptic ulcer disease. We conclude that probably, the host genetic polymorphisms exert influence in the course and gravity of gastric diseases. It is hoped that the results of this work may contribute soon, to the prevention of these diseases and for a more appropriate and effective therapy, this because the knowledge of the molecular basis of the host and the microorganism enables the development of molecular tests that may to be applied toward a correct prognosis of gastric pathologies.

Orientador: Ricardo Barini / Tese (doutorado) - Universidade Estadual de Campinas. Faculdade de Ciências Médicas / Made available in DSpace on 2018-08-16T03:43:19Z (GMT). No. of bitstreams: 1 Machado_IsabelaNelly_D.pdf: 3476920 bytes, checksum: d5a5716fb5a528c323d17a22ef6c28d0 (MD5) Previous issue date: 2010 / Resumo: Introdução: Para uma parcela significativa de fetos com defeitos congênitos o diagnóstico sindrômico permanece indefinido, dificultando a abordagem perinatal, o estabelecimento de prognóstico e o aconselhamento genético. A incapacidade de detecção de pequenas instabilidades genômicas, atualmente apontadas como provável fator causal nestas condições dismórficas, é a principal limitação do estudo cromossômico microscópico pelo bandamento G (cariótipo convencional). A hibridização genômica comparativa (comparative genomic hybridization-CGH) é capaz de identificar perdas e ganhos de material genômico com alta resolução, sem envolver o cultivo celular e o conhecimento prévio da região genômica envolvida. Objetivo: Avaliar a aplicabilidade da técnica de array CGH em sangue fetal para o diagnóstico de perdas e ganhos genômicos em um grupo de fetos dismórficos. Sujeitos/Método: Foi realizado um estudo prospectivo descritivo a partir de amostras sanguíneas de fetos dismórficos e com cromossomos numericamente normais ao bandamento G, admitidos no Setor de Medicina Fetal do Centro de Atenção Integral à Saúde da Mulher (CAISM) da Universidade Estadual de Campinas (Unicamp). Foi realizada a caracterização da amostra estudada e uma análise descritiva dos achados moleculares através da técnica de array CGH. Resultados: Foram incluídos no estudo 50 fetos, dos quais 49 preencheram os critérios de qualidade da técnica. A taxa de detecção de alterações cromossômicas pela técnica de array CGH não detectadas pelo cariótipo convencional foi de 93,7% (45 fetos), e 27% foram consideradas significativas dos pontos de vista citogenético e clínico. Entre os fetos com alterações do número de cópias, 87% apresentaram pelo menos um clone para o qual já estão descritas variações do número de cópias (CNV) em indivíduos fenotipicamente normais. Adicionalmente, a técnica mostrou-se eficaz para o esclarecimento diagnóstico da origem, exata localização e dimensionamento do material adicional encontrado em um feto com anomalia cromossômica estrutural. Conclusões: A caracterização do perfil genômico por array CGH de fetos com defeitos congênitos permitiu complementar o diagnóstico citogenético convencional, aumentando a definição diagnóstica e a identificação de regiões cromossômicas associadas a algumas anomalias congênitas / Abstract: Introduction: A great number of fetuses with congenital defects remain without definitive diagnosis, making difficult the perinatal management, the prognosis establishment and the genetic counseling. The incapacity of detection of short sequence copy number changes, pointed as a probable etiology factor for some congenital defects, is the main limitation of routine G-banding. The Comparative Genomic Hybridization (CGH) overcome this limitation, and also does not require cellular culture or prior knowledge of the involved genomic region. Objective: To evaluate the applicability of the CGH method on fetal material for genomic gains and losses in a group of malformed fetuses. Methods: On a prospective descriptive study, fetal blood samples were collected from malformed fetuses with numerically normal chromosomes at G-banded karyotype, at the Fetal Medicine Unit of the Centro de Atenção Integral à Saúde da Mulher (CAISM) of the Universidade Estadual de Campinas (UNICAMP). Sample characterization and a descriptive analysis of the CGH-based technique results were accomplished. Results: Fifty fetuses were included in this study and 49 were considered optimal according to adopted quality control criteria. The detection rate of fetuses with copy number imbalances not detected by the G-banded karyotype was 93.7% (45 fetuses), with 27% of cytogenetic and clinical significance. Among fetuses with copy number imbalances, 87% presented at least one abnormal clone encompassing CNVs described for phenotipically normal individuals. Additionally, the array CGH showed to be effective for the identification of the additional genetic material origin, with its precise location and size, presented in one fetus with structural chromosomal anomaly. Conclusions: The genomic profile characterization of malformed fetuses through array CGH allowed complementing the conventional cytogenetic diagnosis, obtaining a higher precise diagnosis and the identification of chromosomal regions associated with some congenital anomalies / Doutorado / Tocoginecologia / Doutor em Tocoginecologia

Le Syndrome d’Impatiences Musculaires de l’Éveil (SIME) est une maladie neurologique caractérisée par un besoin urgent de bouger les jambes. C’est également l’une des causes les plus fréquentes d’insomnie. C’est une maladie très répandue, avec une prévalence de presque 15 % dans la population générale. Les maladies multifactorielles comme le SIME sont souvent le résultat de l’évolution d’une composante génétique et d’une composante environnementale. Dans le cadre du SIME, les études d’association génomique ont permis l’identification de 4 variants à effet modéré ou faible. Cependant, ces quatre variants n’expliquent qu’une faible partie de la composante génétique de la maladie, ce qui confirme que plusieurs nouveaux variants sont encore à identifier. Le rôle des déséquilibres génomiques (Copy Number Variations ou CNVs) dans le mécanisme génétique du SIME est à ce jour inconnu. Cependant, les CNVs se sont récemment positionnés comme une source d’intérêt majeur de variation génétique potentiellement responsable des phénotypes. En collaboration avec une équipe de Munich, nous avons réalisé deux études CNVs à échelle génomique (biopuces à SNP et hybridation génomique comparée (CGH)) sur des patients SIME d’ascendance germanique. À l’aide d’une étude cas-contrôle, nous avons pu identifier des régions avec une occurrence de CNVs différentes pour les patients SIME, comparés à différents groupes contrôles. L’une de ces régions est particulièrement intéressante, car elle est concordante à la fois avec des précédentes études familiales ainsi qu’avec les récentes études d’associations génomiques. / Restless Legs syndrome (RLS) is a neurological disorder characterized by the urge to move one’s limbs. It is also one of the most frequent causes of insomnia. The prevalence of RLS is estimated to be around 15% in the general population. Complexes disorders like RLS are often the result of the evolution of genetic and environmental components. For RLS, recent Genome Wide Association Study (GWAS) have identified four variants with mild to moderate effects. However, those four variants explain only a small part of the disease heritability and thus, we expect that many new variants are still to be found. The impact of Copy-Number Variation (CNV) in the genetic mechanism of RLS is still unknown. However, many studies have recently position the CNVs as a significant source of genetic variation potentially responsible of phenotypes. In collaboration with a team from Munich, we conducted two genome-wide CNVs studies (Genome Wide SNP chips and Comparative Genomic Hybridization (CGH)) on RLS patients from Germany. Using cases-controls studies, we identified regions with a different occurrence of CNVs for RLS patients, compared to different groups of controls. One of these regions is particularly interesting, as it has already been identified by both linkage and association studies.

La malformation de Chiari type 1 (MCI) est une anomalie congénitale de la jonction cranio-cérébrale fréquente avec une incidence de 1:1280. MCI est caractérisée par la descente des amygdales cérébelleuses à travers le foramen magnum et est souvent associée à la syringomyélie. Les causes de cette maladie semblent être multifactorielles incluant des facteurs génétiques. La MCI est similaire à une malformation fréquente chez la race des Griffon Bruxellois (GB) connue sous le nom de Malformation Chiari-like (MCL). Le modèle canin offre l’avantage d’une forte homogénéité génétique réduisant ainsi la complexité de la maladie et facilitant l’identification d’un locus causatif. Une étude d’association du génome entier sur une cohorte de 56 GB suivie d’une cartographie fine sur une cohorte de 217 GB a identifié un locus fortement associé à la MCL sur le chromosome 2 (22 SNPs, valeur P= 7 x 10-8) avec un haplotype de 1.9 Mb plus fréquent chez les non affectés. Une seconde étude d’association du génome entier sur une cohorte de 113 GB a permis d’identifier un 2 ème locus fortement associé à la MCL sur le chromosome 13 (25 SNPs , valeur P= 3 x 10 -7) avec un haplotype de 4 Mb surreprésenté chez les non affectés. Ces régions candidates constituent la première étape vers l’identification de gènes causatifs pour la MCL. Notre étude offre un point d’entrée vers une meilleure compréhension des mécanismes moléculaires sous-tendant la pathogénèse de la MCI humaine. / Chiari I malformation (CMI) represents a common congenital abnormality of the craniocerebral junction with an estimated incidence of 1 in 1280. CMI is characterized by a descent of the cerebellar tonsils into the foramen magnum, often in association with syringomyelia. The developmental defect in CMI is thought to be the result of an underdeveloped occipital bone and small posterior fossa. The etiology of CMI is thought to be multifactorial involving genetic factors. CMI in humans is similar to a condition in the dog called Chiari-like malformation (CM) that is particularly common in the Griffon Bruxellois (GB) breeds. A genome wide association study on a 56 GB cohort followed by a fine mapping in a 217 GB cohort have identified a locus on chromosome 2 that was strongly associated with CM (22 SNPs, P value= 7 x 10-8). Haploview analysis of this locus identified a haplotype of 1.9 Mb that was more frequent in non-affected dogs. A second genome wide association study in a 113 GB cohort lead to the identification of another locus on chromosome 13 that was strongly associated with CM (25 SNPs , P value= 3 x 10-7). Analysis of this region identified a 4Mb haplotype that was more frequent in non-affected dogs. Our study constitutes the first essential step towards identification of the causative genes in CM. Our study provides an entry point for better understanding of the molecular genetic mechanisms underlying the pathogenesis of human CMI.

La thèse examine les liens entre la vision pluraliste de la science et l’éthique de la médecine tibétaine et les nouvelles pratiques en médecine occidentale, soit la longévité et la recherche sur la génétique amélioratrice. Elle cherche à cerner l’apport que la médecine tibétaine peut apporter aux recherches occidentales sur la longévité et la génétique humaine amélioratrice. Elle traite donc d’un enjeu social clé et du débat qui s’y rattache. La découverte et la description sont centrales à la méthodologie et informent l’analyse. Nous avons examiné dans un premier temps, les travaux de recherche sur la longévité reliée à la génétique amélioratrice (mémoire et muscles). Nous nous sommes penchés également sur les fondements de la médecine tibétaine en tant que système intégré. Pour ce faire, nous avons traité des notions telles que la santé, l’identité, la perfection et l’immortalité. Notre cadre conceptuel repose sur la théorie bouddhiste de l’interdépendance qui se caractérise par la formulation de catégories qui ensuite sont synthétisées dans l’essence; les deux niveaux d’interprétation de la théorie sont décrits en détail avant de passer à une comparaison avec la notion de complexité occidentale. La médecine tibétaine de fait présente un système où l’éthique et la science sont intégrées et se prête bien à une comparaison avec la vision pluraliste de la science à partir d’une perspective éthique/bioéthique. Les commentaires recueillis auprès des experts nous ont permis de cerner comment la science, l’éthique et l’amélioration de la longévité sont définies au sein des deux paradigmes de l’Est et de l’Ouest. Nos résultats montrent six points qui se dégagent au terme de cette recherche permettent de jeter un pont sur la vision pluraliste de ces paradigmes. Ceux-ci transcendent les points de vue doctrinaux individuels de religions ainsi que du monde scientifique occidental. Plus que tout, ils laissent entrevoir un cadre de références novatrices qui contribuera à la prise de décision à l’égard de questionnements bioéthiques. / This thesis identified and examined the links between the pluralist vision of Western science and the ethical studies of Tibetan medicine, and sought to determine how the bridging of pluralistic visions with Tibetan medicine might contribute to Western research on longevity and human genetic enhancement. The investigation focused on the current debate in these latter two fields. Discovery and description were central to the methodology and informed the analysis. Initially, we examined the research on longevity related to human genetic enhancement (memory and muscle), which addresses the limitation of the physical body, and explored its ramifications through such concepts as healthism, identity, perfection and immortality. Then examining the foundation of Tibetan medicine as an integrated system, we contrasted contemporary longevity research with the Eastern model, in which individual existence and experience escape limitations. We further addressed brain science research and the Tibetan medicine continuum, the unique quality of the latter being that the mind is used as a tool and is philosophically linked with Buddhism. Finally, utilizing the Buddhist conceptual framework of the interdependent theory, which is characterized by formulating categories of phenomena that are then synthesized into their essence, the theory’s two levels of the interpretation of phenomenal reality were described in detail before moving to a comparison with notions of Western complexity. Tibetan medicine employs an integrated system in which ethics and science are interwoven, providing the base for a comparison with the pluralist vision of science from an ethics/bioethics perspective. The insights gathered from interviews with experts in various fields highlighted how science, ethics and longevity enhancement can be addressed within these two paradigms. The research findings led to six points that bridge both the Eastern and Western paradigms by transcending the doctrinal standpoints of individual religions, ethical systems and sciences, and laying the basis for an innovative framework by providing concrete reference elements for decision-making in regard to bioethical questionings.

La malformation de Chiari type 1 (MCI) est une anomalie congénitale de la jonction cranio-cérébrale fréquente avec une incidence de 1:1280. MCI est caractérisée par la descente des amygdales cérébelleuses à travers le foramen magnum et est souvent associée à la syringomyélie. Les causes de cette maladie semblent être multifactorielles incluant des facteurs génétiques. La MCI est similaire à une malformation fréquente chez la race des Griffon Bruxellois (GB) connue sous le nom de Malformation Chiari-like (MCL). Le modèle canin offre l’avantage d’une forte homogénéité génétique réduisant ainsi la complexité de la maladie et facilitant l’identification d’un locus causatif. Une étude d’association du génome entier sur une cohorte de 56 GB suivie d’une cartographie fine sur une cohorte de 217 GB a identifié un locus fortement associé à la MCL sur le chromosome 2 (22 SNPs, valeur P= 7 x 10-8) avec un haplotype de 1.9 Mb plus fréquent chez les non affectés. Une seconde étude d’association du génome entier sur une cohorte de 113 GB a permis d’identifier un 2 ème locus fortement associé à la MCL sur le chromosome 13 (25 SNPs , valeur P= 3 x 10 -7) avec un haplotype de 4 Mb surreprésenté chez les non affectés. Ces régions candidates constituent la première étape vers l’identification de gènes causatifs pour la MCL. Notre étude offre un point d’entrée vers une meilleure compréhension des mécanismes moléculaires sous-tendant la pathogénèse de la MCI humaine. / Chiari I malformation (CMI) represents a common congenital abnormality of the craniocerebral junction with an estimated incidence of 1 in 1280. CMI is characterized by a descent of the cerebellar tonsils into the foramen magnum, often in association with syringomyelia. The developmental defect in CMI is thought to be the result of an underdeveloped occipital bone and small posterior fossa. The etiology of CMI is thought to be multifactorial involving genetic factors. CMI in humans is similar to a condition in the dog called Chiari-like malformation (CM) that is particularly common in the Griffon Bruxellois (GB) breeds. A genome wide association study on a 56 GB cohort followed by a fine mapping in a 217 GB cohort have identified a locus on chromosome 2 that was strongly associated with CM (22 SNPs, P value= 7 x 10-8). Haploview analysis of this locus identified a haplotype of 1.9 Mb that was more frequent in non-affected dogs. A second genome wide association study in a 113 GB cohort lead to the identification of another locus on chromosome 13 that was strongly associated with CM (25 SNPs , P value= 3 x 10-7). Analysis of this region identified a 4Mb haplotype that was more frequent in non-affected dogs. Our study constitutes the first essential step towards identification of the causative genes in CM. Our study provides an entry point for better understanding of the molecular genetic mechanisms underlying the pathogenesis of human CMI.

La thèse examine les liens entre la vision pluraliste de la science et l’éthique de la médecine tibétaine et les nouvelles pratiques en médecine occidentale, soit la longévité et la recherche sur la génétique amélioratrice. Elle cherche à cerner l’apport que la médecine tibétaine peut apporter aux recherches occidentales sur la longévité et la génétique humaine amélioratrice. Elle traite donc d’un enjeu social clé et du débat qui s’y rattache. La découverte et la description sont centrales à la méthodologie et informent l’analyse. Nous avons examiné dans un premier temps, les travaux de recherche sur la longévité reliée à la génétique amélioratrice (mémoire et muscles). Nous nous sommes penchés également sur les fondements de la médecine tibétaine en tant que système intégré. Pour ce faire, nous avons traité des notions telles que la santé, l’identité, la perfection et l’immortalité. Notre cadre conceptuel repose sur la théorie bouddhiste de l’interdépendance qui se caractérise par la formulation de catégories qui ensuite sont synthétisées dans l’essence; les deux niveaux d’interprétation de la théorie sont décrits en détail avant de passer à une comparaison avec la notion de complexité occidentale. La médecine tibétaine de fait présente un système où l’éthique et la science sont intégrées et se prête bien à une comparaison avec la vision pluraliste de la science à partir d’une perspective éthique/bioéthique. Les commentaires recueillis auprès des experts nous ont permis de cerner comment la science, l’éthique et l’amélioration de la longévité sont définies au sein des deux paradigmes de l’Est et de l’Ouest. Nos résultats montrent six points qui se dégagent au terme de cette recherche permettent de jeter un pont sur la vision pluraliste de ces paradigmes. Ceux-ci transcendent les points de vue doctrinaux individuels de religions ainsi que du monde scientifique occidental. Plus que tout, ils laissent entrevoir un cadre de références novatrices qui contribuera à la prise de décision à l’égard de questionnements bioéthiques. / This thesis identified and examined the links between the pluralist vision of Western science and the ethical studies of Tibetan medicine, and sought to determine how the bridging of pluralistic visions with Tibetan medicine might contribute to Western research on longevity and human genetic enhancement. The investigation focused on the current debate in these latter two fields. Discovery and description were central to the methodology and informed the analysis. Initially, we examined the research on longevity related to human genetic enhancement (memory and muscle), which addresses the limitation of the physical body, and explored its ramifications through such concepts as healthism, identity, perfection and immortality. Then examining the foundation of Tibetan medicine as an integrated system, we contrasted contemporary longevity research with the Eastern model, in which individual existence and experience escape limitations. We further addressed brain science research and the Tibetan medicine continuum, the unique quality of the latter being that the mind is used as a tool and is philosophically linked with Buddhism. Finally, utilizing the Buddhist conceptual framework of the interdependent theory, which is characterized by formulating categories of phenomena that are then synthesized into their essence, the theory’s two levels of the interpretation of phenomenal reality were described in detail before moving to a comparison with notions of Western complexity. Tibetan medicine employs an integrated system in which ethics and science are interwoven, providing the base for a comparison with the pluralist vision of science from an ethics/bioethics perspective. The insights gathered from interviews with experts in various fields highlighted how science, ethics and longevity enhancement can be addressed within these two paradigms. The research findings led to six points that bridge both the Eastern and Western paradigms by transcending the doctrinal standpoints of individual religions, ethical systems and sciences, and laying the basis for an innovative framework by providing concrete reference elements for decision-making in regard to bioethical questionings.

Le Syndrome d’Impatiences Musculaires de l’Éveil (SIME) est une maladie neurologique caractérisée par un besoin urgent de bouger les jambes. C’est également l’une des causes les plus fréquentes d’insomnie. C’est une maladie très répandue, avec une prévalence de presque 15 % dans la population générale. Les maladies multifactorielles comme le SIME sont souvent le résultat de l’évolution d’une composante génétique et d’une composante environnementale. Dans le cadre du SIME, les études d’association génomique ont permis l’identification de 4 variants à effet modéré ou faible. Cependant, ces quatre variants n’expliquent qu’une faible partie de la composante génétique de la maladie, ce qui confirme que plusieurs nouveaux variants sont encore à identifier. Le rôle des déséquilibres génomiques (Copy Number Variations ou CNVs) dans le mécanisme génétique du SIME est à ce jour inconnu. Cependant, les CNVs se sont récemment positionnés comme une source d’intérêt majeur de variation génétique potentiellement responsable des phénotypes. En collaboration avec une équipe de Munich, nous avons réalisé deux études CNVs à échelle génomique (biopuces à SNP et hybridation génomique comparée (CGH)) sur des patients SIME d’ascendance germanique. À l’aide d’une étude cas-contrôle, nous avons pu identifier des régions avec une occurrence de CNVs différentes pour les patients SIME, comparés à différents groupes contrôles. L’une de ces régions est particulièrement intéressante, car elle est concordante à la fois avec des précédentes études familiales ainsi qu’avec les récentes études d’associations génomiques. / Restless Legs syndrome (RLS) is a neurological disorder characterized by the urge to move one’s limbs. It is also one of the most frequent causes of insomnia. The prevalence of RLS is estimated to be around 15% in the general population. Complexes disorders like RLS are often the result of the evolution of genetic and environmental components. For RLS, recent Genome Wide Association Study (GWAS) have identified four variants with mild to moderate effects. However, those four variants explain only a small part of the disease heritability and thus, we expect that many new variants are still to be found. The impact of Copy-Number Variation (CNV) in the genetic mechanism of RLS is still unknown. However, many studies have recently position the CNVs as a significant source of genetic variation potentially responsible of phenotypes. In collaboration with a team from Munich, we conducted two genome-wide CNVs studies (Genome Wide SNP chips and Comparative Genomic Hybridization (CGH)) on RLS patients from Germany. Using cases-controls studies, we identified regions with a different occurrence of CNVs for RLS patients, compared to different groups of controls. One of these regions is particularly interesting, as it has already been identified by both linkage and association studies.