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Caracterização Citogenética Molecular de Rearranjos Cromossômicos Aparentemente Equilibrados Associados ao Fenótipo de Infertilidade / Molecular Cytogenetic Characterization of Apparently Balanced Chromosomal Rearrangements Associated with InfertilityJuliana Dourado Grzesiuk 13 August 2012 (has links)
A translocação recíproca é o rearranjo equilibrado mais comum em humanos. Frequentemente, indivíduos com rearranjos equilibrados não apresentam manifestações clínicas, entretanto, na meiose, o pareamento entre cromossomos translocados forma uma figura quadrivalente em forma de cruz que torna a disjunção cromossômica incerta e dependendo do rearranjo, o individuo pode vir a ser infértil, apresentar um risco aumentado de abortamento espontâneo e/ou da prole apresentar alterações fenotípicas. Neste projeto, investigamos duas famílias de pacientes inférteis, portadores de translocações cromossômicas. O objetivo foi caracterizar as alterações citogenéticas e citogenômicas relacionadas à infertilidade masculina em pacientes portadores de rearranjos aparentemente equilibrados, associando técnicas de citogenética clássica (bandeamento GTG), citogenética molecular (FISH) e citogenômica (array-CGH). Foram estudados sete indivíduos da família 1, sendo diagnosticados três portadores da translocação (X;22), sendo um deles azoospérmico. Nesta família foram ainda detectados dois casos de mosaicismo para síndrome de Turner. A família 2 foi composta por dois irmãos oligozoospérmicos, portadores de translocação (8;13). Com a aplicação da técnica de FISH, definimos o cariótipo final dos portadores dos rearranjos como 46,XX ou 46,XY,t(X;22)(p22.3;q11.2) para a família 1 e 46,XY,t(8;13)(q13;q14)para a família 2. A técnica de array-CGH (plataforma 2x400K, Agilent) detectou alterações no número de cópias de alguns genes candidatos relacionados ao fenótipo de infertilidade, sendo a sequência 132 de piRNAs, os genes DDX11, Jagged 2 e ADAM18 na família 1 e os genes candidatos ADAM18 e POTE nos pacientes da família 2. / Reciprocal translocations are the most common balanced rearrangement in humans. Often individuals with balanced rearrangements show no clinical findings. However, in meiosis, the pairing between translocated chromosomes forms a quadrivalent cross-shaped figure which has the effect of making chromosome disjunction uncertain and, depending on the rearrangement, and on the segregation of the unbalanced chromosomes, the individual can be infertile, can present with an increased risk of spontaneous abortions or can have an offspring with abnormal phenotype. We have studied two families of infertile patients, who were carriers of chromosomal translocations. The objective was to characterize the cytogenetic and cytogenomic alterations related to male infertility in patients with apparently balanced rearrangements using classical cytogenetic techniques (GTG banding), molecular cytogenetics (FISH) and cytogenomics (array-CGH). Seven subjects of the family 1 were studied, including three carriers of translocation (X;22), one azoospermic. Two cases of mosaicism for Turner syndrome were detected in this family. The second family consisted of two oligozoospermic brothers with translocation (8;13). FISH was used to characterize the karyotypes as 46, XX or 46,XY, t(X;22)(p22.3;q11.2) for the members of the family 1 and 46,XY,t(8;13)(q13;q14) for family 2. Array-CGH was also performed using the Agilent platform 2x400K, to detect associated copy number variations of some of the candidate genes that could be related to infertility. In the family 1 the candidate genes were 132 piRNAs sequences and DDX11,Jagged 2 and ADAM18 genes. The candidate genes for the family 2 were ADAM18 and POT.
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Altérations moléculaires dans l'adénocarcinome du pancréas / Molecular genetic alterations in pancreatic adenocarcinomaBirnbaum, David 19 December 2014 (has links)
Le cancer du pancréas est un problème majeur de santé publique. Le mauvais pronostic de l'adénocarcinome du pancréas est lié à un diagnostic tardif, une progression rapide, et à une mauvaise réponse aux traitements médicaux disponibles. Une caractérisation complète des altérations génétiques moléculaires sont aujourd'hui nécessaires pour permettre une détection plus précoce et identifier/élaborer de nouvelles thérapies ciblées dans le traitement de l'ADK du pancréas. En utilisant la technique d'hybridation génomique comparative, nous avons étudié les altérations du génome de 39 ADK. Plusieurs pertes récurrentes ont été observées, ainsi que des gains de matériel génétique. A partir de ces résultats, nous avons voulu aller plus loin en identifiant les gènes qui pourraient avoir des conséquences au niveau transcriptomique. A partir de données publiques, nous avons comparé les profils d'expression d'ADK (n=419) et de pancréas normal (n=105). Parmi les gènes trouvés amplifiés et/ou gagnés par aCGH, 170 (48%) étaient surexprimés dans les ADK par rapport au tissus normal. Les principales voies de signalisation impliquées touchaient la régulation du cycle cellulaire, les voies TP53 et TGFß. Parmi les gènes délétés en aCGH, 141 (41%) étaient sous exprimés dans les ADK du pancréas par rapport au tissus normal et étaient essentiellement liés au « métabolome » de la cellule pancréatique. Enfin, nous avons identifié une dizaine de gènes dont l'expression pourrait être liée à la survie des patients. Certains de ces gènes pourraient être des candidats à tester en tant que biomarqueurs pronostic ou cibles pour le développement de nouvelles thérapeutiques. / Pancreatic adenocarcinoma (PDCA) is a major public health problem in France and worldwide. The inoperability and the poor prognosis of the PDCA are due to late diagnosis, rapid tumor progression (>80% of patients displayed metastases at diagnosis), early recurrences after resection, and poor response to available therapies. Innovative approaches and a comprehensive characterization of molecular genetic alterations are dearly needed to help develop techniques of early detection, identify new molecular targets and devise novel targeted-therapies (Hidalgo, 2010). Using high-resolution array-comparative genomic hybridization (aCGH), we studied the genome alterations of 39 fine-needle aspirations from PDCA. Recurrent losses were observed and comprised several known tumor suppressor genes. We identified frequent genetic gains. With this study, we decided to go one step further by identifying genes that might also be deregulated at the transcriptomic level. We started our analysis with a population of PDCA (n=419) versus normal pancreas (n = 105). Among the 352 genes found amplified and/or gained by aCGH, 170 (48%) were up regulated at the transcriptional level in PDCA compared to normal pancreatic tissues. Major pathways involved were cell cycle, TP53 and TGFß. Among the genes located in regions of losses, 141 (41%) were down regulated in PDCA compared to normal tissues. Furthermore, some genes were found related to a patients' survival With this study, we highlighted novels genes associated to PDCA oncogenesis. Some of those candidates should be further investigated as prognosis markers or as potential targets for new therapeutic approaches.
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Optical Alignment with CGH Phase ReferencesFrater, Eric, Frater, Eric January 2016 (has links)
The growing field of high-order aspheric and freeform optical fabrication has inspired the creation of optical surfaces and systems which are difficult to align. Advances in optical alignment technology are critical to fabricating and integrating aspheric components in advanced optical systems. This dissertation explores the field of optical alignment with a computer-generated hologram (CGH) used as a reference. A CGH is a diffractive optic which may be used to create a desired phase profile across a beam of light, project irradiance patterns, or serve as a mask for an incident beam. The alignment methods presented in this dissertation are concerned with the use of a CGH to create reference phase profiles, or "wavefronts" , in a beam. In one application a set of axisymmetric CGH references are co-aligned. Each CGH has also been aligned to an aspheric mirror so the co-alignment of the CGH references is also a co-alignment of the aspheric mirrors. Another application is concerned with aligning an interferometer to test an aspheric mirror surface. The interferometer measures a "null" interference pattern when its wavefront accommodates a known surface profile. In this alignment application the CGH creates wavefronts which accommodate a known set of small spherical reference features at the test surface. An interference null from all the "phase fiducial" reference features indicates an aligned projection of the CGH. The CGH co-alignment method is implemented on a 4-mirror prime focus corrector known as the Hobby-Eberly Telescope Wide Field Corrector (HET WFC). It is shown that this method was very successful for centration alignment of some mirrors, whereas mechanical stability was the hardware limitation for other degrees of freedom. The additional alignment methods used in this project are described in detail and the expected alignment of the HET WFC is reported.The fabrication, characterization and application of spherical phase fiducials is demonstrated in a CGH-corrected Fizeau test prototype. It is shown that these reference features achieve <±1.5µm transverse alignment precision. A pair of phase fiducials is also applied to constrain the clocking and magnification of a projected wavefront. Fabrication and coordinate measurement of the features present the dominant challenges in these demonstrations.
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Array-CGH bei Kindern mit Entwicklungsstörung oder geistiger Behinderung: Bei welcher Konstellation finden sich gehäuft klinisch relevante Chromosomenaberrationen? / Array CGH in patients with developmental or intellectual disability: are there phenotypic clues to pathogenic copy number variations?Klein, Nina 25 January 2017 (has links)
No description available.
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Caractérisation de lignées de médulloblastomes par cytogénétique moléculaire dans le but d'étudier les mécanismes sous-jacents d'apparition et de propagation des cellules tumoralesDubé, Sophie January 2002 (has links)
Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.
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Improving DNA quality using FFPE tissues for Array Comparative Genomic Hybridization to find Single Nucleotide Polymorphisms (SNPs) in MelanomaPotluri, Keerti 28 August 2015 (has links)
No description available.
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Etude des relations génotype/phénotype dans le rétinoblastome / Study of the relationship genotype/phenotype in retinoblastomaCastéra, Laurent 22 November 2012 (has links)
Le rétinoblastome est une tumeur rare qui touche la rétine du jeune enfant. L’inactivation bi-allélique du gène RB1 est à l’origine du développement tumoral. RB1 est le premier gène suppresseur de tumeur qui ait été identifié et la prédisposition au rétinoblastome constitue un véritable paradigme de la prédisposition aux cancers. Dans les formes non prédisposées génétiquement, les deux mutations apparaissent dans une cellule rétinienne unique ; le rétinoblastome est alors unilatéral. Dans les formes à prédisposition génétique, la première mutation est constitutionnelle et la deuxième est somatique. La mutation constitutionnelle est une néo-mutation pré- ou post- zygotique dans les formes sporadiques, alors qu’elle est héritée dans les formes familiales. Dans les formes avec prédisposition génétique, le diagnostic est plus précoce que dans les formes sans prédisposition et la bilatérisation du rétinoblastome est généralement la règle. Néanmoins, de rares familles présentent une pénétrance réduite et une variabilité phénotypique se traduisant par la coexistence de patients atteints de rétinoblastome bilatéral ou unilatéral, d’apparentés porteurs sains et d’apparentés présentant des rétinomes. Les mécanismes responsables de la variabilité phénotypique intrafamiliale sont inconnus et l’existence de facteurs génétiques modulant le phénotype tumoral est probable.L’origine de la variabilité de l’expression phénotypique du rétinoblastome peut être la résultante (i) de l’existence de mutations en mosaïque, (ii) de mutations de RB1 et (iii) de facteurs modificateurs génétiques indépendants du locus de RB1. Trois axes distincts et originaux basés sur ces origines possibles de variabilité phénotypique ont été développés pour caractériser les relations génotype/phénotype dans le rétinoblastome. Premièrement, les conséquences d’une mosaïque somatique ont été illustrées grâce à l’étude d’une famille ayant bénéficié de cinq diagnostics prénatals. Dans ces familles, certains fœtus porteurs de l’allèle à risque identifié par une approche indirecte basée sur l’étude de microsatellites au locus de RB1, n’étaient pas porteurs de la mutation du parent atteint, lui-même atteint d’un rétinoblastome bilatéral. Ainsi, nous avons démontré la présence d’une mosaïque somatique et gonadique chez ce parent lourdement atteint. La conséquence de l’existence de patients présentant une mosaïque dans le cadre du conseil génétique a été discutée. La suite de nos travaux a pris en compte ces résultats afin de limiter les biais que pourrait induire la présence de mutations en mosaïque dans des études de corrélation génotype/phénotype dans le rétinoblastome. Deuxièmement, l’association de grandes délétions emportant RB1 avec des retards psychomoteurs chez des patients atteints de rétinoblastome a été étudiée. Une approche de CGH hautement résolutive, ciblée sur le locus de RB1, a été mise en place afin de caractériser le rôle des gènes contigus de RB1 dans ce syndrome. Ainsi, cette approche a permis de définir une zone à risque de retard psychomoteur que nous proposons comme seuil d’alerte pour le généticien. Cette zone définit un gène, PCDH8 d’expression cérébrale exclusive, comme un excellent candidat au retard psychomoteur. Enfin, troisièmement, une approche « gène candidat » reposant sur l’étude du SNP309 du promoteur de MDM2, a été mise en œuvre. / Retinoblastoma is the most common intraocular childhood cancer and occurs when both alleles of the RB1 gene are inactivated in the retina. In patients without genetic predisposition, the two mutations occurred in a single unique retinal cell. In subjects with a genetic predisposition to retinoblastoma, the first RB1 mutation is found in the germline and the second appears as a somatic mutation. Germline carriers usually develop bilateral or multifocal tumors and the diagnosis is earlier. However, some rare families exhibit low penetrance and variable expressivity of the disease because bilaterally affected, unilaterally affected, and unaffected mutation carriers are known to coexist. The existence of genetic modifiers in retinoblastoma therefore appears highly probable and must be considered. The lack of penetrance and the variable expressivity could be the sum of three independent causes. The presence of a mosaic can affect the phenotype, the nature of the mutation can drive low penetrance and particular phenotype like psychomotor delay in case of large genomic deletions and genetic modifier factors could modulate the phenotype. These three major keys have been studied in order to highlight the relations between the phenotype and the genotype. Firstly, the consequences of mosaicism have been illustrated by a prenatal diagnosis concerning a couple with a bilateral retinoblastoma-affected male patient who requested five successive prenatal diagnoses and in whom RB1 mutation mosaicism had important implications. Implications of mosaicism in genetic counseling have been discussed and taken into consideration in order to limit bias in the two following genotype/phenotype studies. Secondly, the association between whole germline monoallelic deletions of the RB1 gene and psychomotor delay was studied by a high-resolution CGH array focusing on RB1 and its flanking region. Comparative analysis detected a four megabase critical interval including a candidate gene, protocadherin 8 (PCDH8). PCDH8 is thought to function in signaling pathways and cell adhesion in a central nervous system-specific manner, making loss of PCDH8 one of the probable causes of psychomotor delay in RB1-deleted patients. Thirdly, a candidate gene approach based on partners that are necessary for the development of the tumor attempted to find possible genetic modifiers. MDM2, which increases p53 and pRB catabolism, was therefore a prominent candidate. The minor allele of MDM2 that includes a 309T>G transversion (SNP rs2279744) in the MDM2 promoter is known to enhance MDM2 expression. In family-based association analyses performed in 70 retinoblastoma families, the MDM2 309G allele was found to be statistically significantly associated with incidence of bilateral or unilateral retinoblastoma among members of retinoblastoma families under a recessive model (Z = 3.305, two-sided exact P = .001). The strong association of this genotype with retinoblastoma development designates MDM2 as the first modifier gene to be identified among retinoblastoma patients
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Chromosomale Imbalancen invasiv duktaler und invasiv lobulärer Mammakarzinome detektiert mittels komparativer genomischer Hybridisierung (CGH)Richard, Frank 13 December 1999 (has links)
Das Ziel der vorliegenden Arbeit bestand in der molekularzytogenetischen Charakterisierung von invasiv duktalen und invasiv lobulären Mammakarzinomen sowie der Identifizierung unterschiedlicher genetischer Alterationsmuster in Tumorsubgruppen der invasiv duktalen Mammakarzinome. Mit Hilfe der komparativen genomischen Hybridisierung (CGH) wurden 30 invasiv duktale und 20 invasiv lobuläre Mammakarzinome auf genetische Veränderungen untersucht. In beiden Tumorarten überwiegen DNA-Deletionen gegenüber DNA-Gewinnen, daher scheint die Inaktivierung tumorsupprimierender Gene einen größeren Einfluß auf das maligne Wachstumsverhalten auszuüben. Invasiv duktale Mammakarzinome zeichnen sich durch eine im Mittel größere Anzahl an Alterationen pro Tumorfall aus als invasiv lobuläre Karzinome (14,9 vs. 8,9). Neben einer größeren Anzahl an DNA-Verlusten ist auch die Anzahl der DNA-Überrepräsentierungen deutlich höher verglichen mit invasiv lobulären Mammakarzinomen (6,2 pro Tumorfall vs. 2,7 pro Tumorfall). DNA-Gewinne auf Chromosom 1q und DNA-Verluste auf den Chromosomen 6q, 11q22- qter und 13q fanden sich in >=40% der Fälle in beiden histologischen Tumortypen. In invasiv duktalen Mammakarzinomen traten DNA-Gewinne mit größerer Frequenz auf den Chromosomen 6p, 8q, 11q13, 16p, 17q, 19p/q und 20q auf. Ebenfalls häufiger waren DNA-Deletionen auf den Chromosomen 2q, 3p, 4p/q, 5q, 7p, 8p, 9q, 10q und 15q zu finden. DNA-Verluste auf den Chromosomen 16q, 17p, 18q und 22q wurden dagegen vermehrt in invasiv lobulären Karzinomen detektiert. Gut (G1) und schlecht (G3) differenzierte invasiv duktale Mammakarzinome zeichnen sich durch ein unterschiedliches genetisches Muster aus. Während gut differenzierte Tumore durch DNA-Gewinne auf 1q, 11q11-13, 16p und 20q gekennzeichnet sind, weisen die schlecht differenzierten Tumore zusätzlich DNA-Deletionen im Bereich der Chromosomen 5q, 18q und 21q21 auf. Außerdem läßt sich ein unterschiedliches genetisches Muster bei Östrogenrezeptor- positiven und Östrogenrezeptor-negativen invasiv duktalen Mammakarzinomen feststellen. Die Östrogenrezeptor-negativen Tumore zeigen eine größere Anzahl an Alterationen, dazu gehören zusätzliche DNA-Überrepräsentierungen auf 1p, 6p und 22q und DNA-Verluste der Chromosomen 5q, 7p, 8p und 12q. Somit läßt sich feststellen, daß sich invasiv duktale und invasiv lobuläre Mammakarzinome durch ein wiederkehrendes Muster chromosomaler Veränderungen charakterisieren lassen. / The aim of the study was to analyze invasive ductal and invasive lobular breast carcinomas regarding to molecular DNA imbalances as well as different DNA imbalances in tumor subgroups of the invasive ductal carcinomas. Comparative genomic hybridization (CGH) was applied to analyze 30 invasive ductal and 20 invasive lobular breast carcinomas to carry out genetic alterations. In both tumor subgroups, DNA losses showed a higher incidence compared to DNA gains, suggesting a higher influence of inactivation of tumor suppressor genes in tumor progression. Invasive ductal carcinomas showed a higher incidence of alterations per case compared to invasive lobular carcinomas (14,9 vs. 8,9). Besides a higher incidence of DNA losses, particularly DNA gains were statistically significant in invasive ductal carcinomas (6,2 per tumorcase vs. 2,7 per tumorcase). DNA gains on chromosome 1q and DNA losses on chromosomes 6q, 11q22-qter and 13q were investigated in >=40% of all tumor cases. DNA gains were observed with a higher frequency in invasive ductal carcinomas on 6p, 8q, 11q13, 16p, 17q, 19p/q and 20q. Additionally, DNA losses showed a higher incidence on 2q, 3p, 4p/q, 5q, 7p, 8p, 9q, 10q and 15q compared to invasive lobular carcinomas. In contrast, DNA losses on 16q, 17p, 18q and 22q reached statistical significance in invasive lubular carcinomas. Well-differentiated (G1) and poorly differentiated (G3) invasive ductal carcinomas reflected different genetic imbalances. Well-differentiated carcinomas are associated with DNA gains on 1q, 11q11-13, 16p and 20q, whereas poorly differentiated tumors showed additional DNA losses on 5q, 18q and 21q21. Furthermore, the investigation indicated that the average number of alterations is correlated also to the estrogen receptor content of the invasive ductal carcinomas. Tumors with estrogen receptor negative content showed a higher incidence of alterations on the following regions, i.e., DNA gains on 1p, 6p and 22q and DNA losses on 5q, 7p, 8p and 12q. Consequently, invasive ductal and invasive lobular carcinomas are characterized by distinct patterns of chromosomal alterations.
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Estudo de genes candidatos aos Transtornos do Espectro Autista / Study of candidate genes to Autism Spectrum DisordersRibeiro, Cintia Marques 07 June 2013 (has links)
Os transtornos do espectro autista (TEA) são condições neuropsiquiátricas caracterizadas por padrões comportamentais estereotipados, ausência ou limitação de comunicação verbal e de interação social recíproca. Diversos estudos têm mostrado que esses transtornos possuem etiologia genética complexa e heterogênea, o que dificulta a identificação dos fatores causais. Estima-se que cerca de 70% dos casos de TEA são idiopáticos. Portanto, com o objetivo de identificar mecanismos etiológicos associados aos TEA, utilizamos as seguintes estratégias: customização de uma lâmina de microarray CGH que possibilite a detecção não só de grandes CNVs, mas também de alterações menores do que 10 kbp, em exons e regiões UTR de genes potencialmente candidatos; a comparação entre os tipos de rearranjos detectados em pacientes sindrômicos e em não sindrômicos e, ainda, a investigação mais detalhada de uma família com indivíduos portadores de transtorno autista e síndrome de Asperger. Foram avaliados 103 portadores de TEA não sindrômicos e 18 sindrômicos, sendo as taxas de detecção de alterações potencialmente patogênicas, respectivamente, de 11,6% e 38,9%. Dentre as alterações detectadas 44,4% são menores do que 10 Kbp. Portanto, a estratégia de usar uma lâmina customizada, com alta densidade de sondas complementares aos exons e regiões não codificantes de genes potencialmente envolvidos na etiologia dos TEA, capaz de detectar tanto alterações grandes quanto pequenas, parece ser relevante na tentativa de elucidar o maior número de casos possíveis e melhor compreender esses transtornos. Além disso, essa lâmina também pode ser utilizada como uma ferramenta para auxiliar o diagnóstico clínico e o aconselhamento genético com um custo mais acessível em comparação a outras comerciais ou ao sequenciamento de última geração. Cerca de 33,3% das CNVs observadas afetam região UTR, sugerindo que mutações nessas regiões podem explicar uma proporção significativa dos casos nos quais não são detectadas alterações através de outros testes genômicos, visto que a maioria desses ainda não exploram adequadamente regiões não codificantes. Entre os pacientes autistas não sindrômicos verificou-se que a maioria dos genes afetados por CNVs estão envolvidos em duas principais funções biológicas - sinapses glutamatérgicas e orientação axonal, sugerindo que TEA não sindrômico pode ser causado por disfunção em genes diferentes envolvidos em processos fisiológicos comuns. Diferente do que observamos entre pacientes não sindrômicos, detectamos mais de uma alteração em um mesmo indivíduo ou alterações que englobam mais de um gene entre os pacientes sindrômicos, reforçando o modelo oligogênico para alguns casos de TEA. Por fim, os dados obtidos no estudo da família com portadores de síndrome de Asperger e transtorno autista sugere que a gravidade do quadro clínico possa estar relacionada ao número de mutações e possivelmente por duas mutações diferentes em ambos os alelos de um mesmo gene. Nossos resultados, além de apoiar o envolvimento dos genes MDGA2, FHIT, HTR2A, SHANK2, GRIA3, ZNF778, PRKCα, CDH15, DIAPH3, GCH1, GRM5, MARK1, SLC17A6, IMMP2L, BZRAP1, SYNGAP1, ANK3, MAP1A, GABRR2 e LAMC3 nos TEA também sugere novos genes candidatos: LRRC7, LRRIQ3, CADPS1, NUFIP, SEMA3A, SNAP29, MBD2, GAD2, DGKH e PARD3 / The autism spectrum disorders (ASD) are neuropsychiatric conditions typically characterized by social deficits, communication difficulties, stereotyped or repetitive behaviors and interests. Several studies have shown that these disorders have a complex and heterogeneous genetic etiology, which makes difficult to identify the causal factors. Approximately 70% of cases are idiopathic. In order to identify etiological mechanisms associated with ASD, we have used the following strategies: customized a microarray CGH platform that allows detection not only of large CNVs, but also alterations smaller than 10 kbp in exons and UTR regions of potential candidate genes, the comparison between the types of rearrangements detected in syndromic and non-syndromic patients and further, more detailed investigation of a family segregating both autistic disorder and Asperger syndrome. We evaluated 103 nonsyndromic and 18 syndromic patients by the custom-designed array and the detection rate of possibly pathogenic alterations were, respectively, 11.6% and 38.9%. Among these CNVs, 44.4% are smaller than 10 kbp. Therefore, the strategy of using a custom-designed array, enriched with probes targeted to genes potentially involved in the ASD etiology and able to detect both large and small CNVs, seems to be relevant in an attempt to elucidate the largest number of cases and to better understand these disorders. Furthermore, this platform can also be used as a tool to support the clinical diagnosis and genetic counseling with a more affordable cost compared to conventional other or next-generation sequencing. Approximately 33.3% of the observed CNVs affect UTR region, suggesting that mutations in non-coding regions might explain a significant proportion of ASD cases negative for most genomic screenings, which still do not explore adequately these regions. Among nonsyndromic autistic patients we found that most of the genes affected by CNVs are involved in two main biological functions - glutamatergic synapses and axonal guidance, suggesting that nonsyndromic ASD can be caused by dysfunction in different genes of a few common physiological processes. In contrast to our findings in nonsyndromic patients, we detected more than one alteration in a single individual or alterations that involve more than one gene among the syndromic patients, reinforcing the oligogenic model for some cases of ASD. Finally, the data obtained in the study of the family segregating both Asperger syndrome and autistic disorder suggests that the severity of ASD seems to be modulated by the number of hits and possibly by hits in both alleles of the same gene. Our results support the involvement of genes MDGA2, FHIT, HTR2A, SHANK2, GRIA3, ZNF778, PRKCα, CDH15, DIAPH3, GCH1, GRM5, MARK1, SLC17A6, IMMP2L, BZRAP1, SYNGAP1, ANK3, MAP1A, GABRR2 and LAMC3 in ASD etiology and also suggests new candidates: LRRC7, LRRIQ3, CADPS1, NUFIP, SEMA3A, SNAP29, MBD2, GAD2, DGKH and PARD3
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Determinação das alterações genômicas em pacientes com malformações congênitasOliveira, Jakeline Santos January 2018 (has links)
Orientador: Danilo Moretti-Ferreira / Resumo: As ACs são alterações visíveis nos cromossomos, classificadas como numéricas e estruturais. Atualmente o grande desafio da genética clínica é classificar e associar a relevância clínica dos desequilíbrios genéticos ao fenótipo dos portadores. O trabalho tem como objetivo principal caracterizar desequilíbrio genômico sem diagnóstico sindrômico previamente descritos pelas técnicas de citogenética clássica, molecular visando apurar os pontos de quebras e genes inseridos na região cromossômica alterada por meio da citogenômica em estudos de casos. Foram feitas análises por citogenética (bandamento GTG), citogenética molecular (FISH) e citogenômica (array-CGH) em três pacientes com malformações congênitas não-sindrômicas para definição diagnóstica e maior conhecimento sobre a correlação genótipo-fenótipo. Foram redigidos estudos de casos de três pacientes portadores de MCs, atraso do desenvolvimento e deficiência intelectual. O primeiro copilado de caso trata-se de paciente do sexo feminino com anomalias esqueléticas, deficiência intelectual e atraso do desenvolvimento. O cariótipo da paciente é 46,XX[11]/47,XX,+mar[9]. A análise de array-CGH revelou dois ganhos/duplicações nas bandas cromossômicas 6p11.2q12 (10.335 Mb de tamanho) e 6q14.1q14.3 (10.765 Mb de tamanho). Por meio da técnica da FISH e os resultados do array-CGH a região duplicada 6q14.1q14.3 encontra-se inserida em um cromossomo marcador, oriundo do cromossomo 6. Os sinais clínicos descritos na paciente foram semelhan... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The ACs are visible changes in the chromosomes, classified as numerical and structural. Currently the great challenge of clinical genetics is to classify and associate the clinical relevance of genetic imbalances with the phenotype of the carriers. The main objective of this work is to characterize genomic imbalance without syndromic diagnosis previously described by the classical and molecular cytogenetic techniques, in order to determine the breakpoints and genes inserted in the chromosomal region altered by cytogenetics in case studies. Cytogenetics (GTG banding), molecular cytogenetics (FISH) and cytogenetics (array-CGH) were performed in three patients with non-syndromic congenital malformations for diagnostic definition and greater knowledge on genotype-phenotype correlation. Case studies of three patients with MCs, developmental delay and intellectual disability were written. The first case file is a female patient with skeletal anomalies, intellectual disability and developmental delay. The patient's karyotype is 46, XX [11] / 47, XX, + sea [9]. The array-CGH analysis revealed two gains / doublings in the chromosomal bands 6p11.2q12 (10,335 Mb in size) and 6q14.1q14.3 (10,765 Mb in size). Through the FISH technique and the results of the array-CGH the duplicate region 6q14.1q14.3 is inserted in a chromosome marker, coming from chromosome 6. The clinical signs described in the patient were similar to other patients with duplication of the region 6q14. The genes PGM3, M... (Complete abstract click electronic access below) / Mestre
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