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Genetic, Diagnostic and Therapeutic Aspects of Primary AldosteronismNorlela Sukor Unknown Date (has links)
Background: Primary aldosteronism (PAL) has emerged as the commonest specifically treatable and potentially curable form of secondary hypertension. With its propensity towards cardiovascular complications above that expected from hypertension alone, PAL is a potentially highly detrimental state which should be detected as early as possible in the course of the disease and treated appropriately. The detection of earlier, milder, normokalaemic forms of PAL using the aldosterone/renin ratio (ARR) as a screening test has significantly enlarged the clinical spectrum of PAL and facilitated identification of a new familial variety (familial hyperaldosteronism type II, FH-II). Unlike familial hyperaldosteronism type I (FH-I), FH-II is not glucocorticoid remediable and is not caused by the CYP11B1/CYP11B2 “hybrid” gene mutation. The genetic defects underlying FH-II have not yet been elucidated and hence, detection of FH-II still involves complicated and time-consuming biochemical screening by ARR testing and confirmation by carefully performed suppression testing such as fludrocortisone suppression testing. Diagnosing PAL by currently available biochemical methods is tedious. Finding a simple and reliable genetic test for FH-II which could be applied to all members of a family with known FH-II and also to apparently sporadic PAL would simplify patient management. A genome-wide search has already demonstrated linkage of FH-II to chromosome 7p22, consistent with this locus harbouring the causative gene/s for FH-II. Three candidate genes [retinoblastoma-associated Kruppel-associated box gene (RBaK, involved in tumorigenesis and cell cycle control), postmeiotic segregation increased 2 (PMS2, involved in DNA mismatch repair and tumour predisposition) and guanine nucleotide-binding protein alpha-12 (GNA12, a transforming oncogene)] within this linked locus have been examined in an attempt to find the causative mutations for FH-II, but no clear causative mutations have so far been found. PAL continues to be a challenging yet rewarding disease to manage. Although much has been learnt about PAL, there are still many areas which have not been explored. PAL considered due to bilateral autonomous production of aldosterone is usually treated medically because unilateral adrenalectomy has been considered ineffective. Since medical treatment may cause adverse effects or fail to control hypertension, defining the role of unilateral adrenalectomy in bilateral PAL is an important clinical issue, but quality outcome data are lacking. The candidate therefore peformed a retrospective study of the efficacy of unilateral adrenalectomy in patients with bilateral PAL. In patients with unilateral PAL, unilateral laparoscopic adrenalectomy has been shown to correct hypokalaemia and lead to cure or improvement in hypertension control. While most studies have focused on clinical and biochemical outcomes, to the candidate’s knowledge, there are no data on the effects of adrenalectomy on quality of life (QOL). Assessing the QOL in patients with unilateral PAL before and after unilateral laparoscopic adrenalectomy (which cured hypokalaemia in all and hypertension in the majority) provided an insight into the degree to which the disease process and/or its treatment affects the life of an individual with PAL. Aims: The overall aims of this thesis were to further explore the genetic basis of FH-II, to examine the role of adrenalectomy in patients with bilateral PAL and the effects of unilateral adrenalectomy on QOL in unilateral PAL as a first step in dissecting out the effects of medical and surgical treatment on QOL in the more common bilateral PAL. In order to address the overall aims, the specific aims of the thesis were (1) to narrow the linked region at 7p22 by phenotyping and genotyping additional FH-II families from Italy, using more closely spaced microsatellite markers at 7p22, and then assess the combined multipoint logarithm of odds (LOD) score for these Italian as well as two Australian and one South American families; (2) to sequence candidate genes in the narrowed linked region for FH-II associated mutations; (3) to assess the role of unilateral adrenalectomy in bilateral PAL and identify predictive parameters; and (4) to assess the quality of life following unilateral adrenalectomy in patients with unilateral PAL. Methods and Results: Two Italian families with FH-II were genotyped using seven closely spaced microsatellite markers at 7p22. All known affected individuals from each of the two Italian families were found to share identical haplotypes for the seven markers, consistent with linkage of the disease locus with the 7p22 region. The multipoint LOD score of the now five known families with FH-II which demonstrate linkage at 7p22, calculated using MERLIN linkage analysis was highly significant at 5.22. Three candidate genes in this linked region were then examined for mutations causing FH-II; the replication protein A 3 (RPA3), zinc finger protein 12 (ZNF12) and glucocorticoid induced transcripts 1 (GLCCI1) genes were selected as they are involved in cell cycle control, and adrenal hyperplasia and adenomas are common in FH-II. Using the method of polymerase chain reaction-sequencing, coding regions, splice sites, proximal promoter, 5’ and 3’ untranslated regions (UTR) were sequenced in affected and unaffected subjects from the 7p22-linked FH-II families. Identified single nucleotide polymorphisms (SNPs) were genotyped to assess significance. For RPA3, four different SNPs were initially found to segregate with the affectation status, that is, they were present in the two affected and not the two unaffected subjects from the largest Australian family (family 1, eight affecteds) with FH-II. However, only two SNPs (rs2024374 G/C and rs17169194 T/G) were further genotyped as that they were in functionally important positions of the gene (that is, in regulatory regions within the promoter and 5’ UTR) and because of the relatively low allele frequency reported in the literature for these two SNPs in controls. Further genotyping of these SNPs was carried out in another six affecteds and four unaffecteds from the same family and a complete segregation of these two SNPs with affectation status was seen in family 1. The G/C mutation rs2024374 in the RPA3 promoter results in the loss of three transcription factor binding sites and creation of one new site. The factors for which the binding sites in the RPA3 promoter and 5’UTR were altered by these two SNPs were involved in regulation of cell differentiation, proliferation and apoptosis. Hence, it is possible that altered activity of the RPA3 promoter and 5’UTR in family 1 could result in predisposition to adrenal hyperplasia or neoplasia, altered ARR and/or hypertension. Genotyping of these SNPs was then carried out in another two pedigrees (families 2 and 3) that showed linkage to 7p22, and in 75 normotensive, non-PAL control subjects. However, neither of these two SNPs segregated with the affectation status in family 2 and 3, and they were present in 30% and 20% of controls, respectively. For ZNF12 and GLCCI1, no evidence of causative mutations was found in the coding regions, splice sites, proximal promoter region and proximal 5’ and 3’ UTR. Between 1984 and 2004, 51 of 684 patients diagnosed with bilateral PAL underwent unilateral adrenalectomy. Forty patients fulfilled the inclusion criteria and were followed for at least 12 (median 56.4) months. Hypertension was cured in 15% and improved in 20%, usually within one year of unilateral adrenalectomy. The proportion with controlled hypertension was significantly (p<0.001) higher after adrenalectomy (65%) than before (25%). Mean systolic (p<0.001) and diastolic (p<0.001) blood pressure, left ventricular mass index (p<0.05) and aldosterone/renin ratio (p<0.001) fell. Serum creatinine independently predicted hypertension cure. From 2007 through 2008, QOL was evaluated prospectively using the internationally validated SF-36 questionnaire before and 3 and 6 months post-operatively in 22 patients [14 males, 8 females; mean age 50.0 ± 2.0 (range 27-69) years] with unilateral PAL who underwent adrenalectomy within the Endocrine Hypertension Centre, Greenslopes and Princess Alexandra Hospitals. Pre-operatively, the SF36 score for each QOL domain was lower for PAL patients than reported for the Australian general population, significantly so for physical functioning (p<0.05), role physical (p<0.001), vitality (p<0.001) and general health (p<0.05). Compared with pre-adrenalectomy, there were significant increments in mean scores at 3 months for physical functioning (p<0.05), role physical (p<0.05), general health (p<0.001), role emotional (p<0.05), social functioning (p<0.05), mental health (p<0.001) and vitality (p<0.001); and at 6 months for physical functioning (p<0.05), role physical (p<0.05), general health (p<0.05), role emotional (p<0.05), mental health (p<0.05) and vitality (p<0.001). Mean SBP and DBP improved significantly (p<0.001), with 86% of these patients cured (BP≤140/90, no drugs) and the remaining 14 % improved. Mean plasma potassium (p<0.001) and renin concentration rose (p<0.01), whereas mean upright plasma aldosterone (p<0.001), aldosterone/renin ratio (p<0.001) and number of antihypertensive agents fell (p<0.001). Conclusion: In the Italian families with FH-II available for study, work by the candidate included in this thesis confirmed linkage of FH-II to chromosome 7p22. The combined multipoint LOD score of 5.22 for the five families showing linkage at 7p22 was highly significant. Linkage to 7p22 in Italian families with FH-II extends the previous positive findings to a third geographical area, bringing greater certainty regarding the importance of this locus in identifying causative mutations. Although no clear causative mutations were found in the three 7p22 candidate genes examined, it is conceivable that the rs2024374 G/C and/or rs17169194 T/G SNPs in RPA3 could act in conjunction with another 7p22 mutation in family 1, resulting in the FH-II phenotype. Examination of the outcome of unilateral adrenalectomy in patients with bilateral PAL suggests that this surgical approach can be beneficial in certain carefully selected patients and should not be automatically excluded as a treatment option. Unilateral adrenalectomy in patients with unilateral PAL has positive impacts not only on clinical and biochemical parameters but also on QOL. The findings of this thesis provide new insights into the genetic basis and therapeutic options and treatment outcomes of PAL and further highlight its importance as a common, genetically based, specifically treatable and potentially curable cause of hypertension and cardiovascular disease. It also points the way to potentially very useful studies in future by exploring longer term effects of unilateral laparoscopic adrenalectomy as treatment for PAL on QOL, to compare unilateral adrenalectomy in those with unilateral versus bilateral PAL, and to compare surgery with specific medical treatment.
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Correlação bioquímica e genes da rota do folato em fissuras oraisPitt, Silvia Brustolin January 2009 (has links)
Introdução: As fissuras de lábio e/ou palato (FL/P) são malformações congênitas comuns na espécie humana, apresentando prevalência de 1/700 recém nascidos vivos, variando de acordo com os diferentes grupos étnicos e fatores sócio-econômicos. As FL/P apresentam padrão complexo de herança, estando envolvidos fatores genéticos e ambientais. Entre os fatores ambientais deficiências de vitaminas já foram descritas, e diversos estudos sugerem que o uso de ácido fólico periconcepcional pode prevenir a recorrência das fissuras orais. Objetivos: Estudar características bioquímicas e polimorfismos em genes da rota metabólica do folato em FL/P não sindrômicas (NS). Métodos: Foram incluídas 140 mulheres (113 mães não afetadas de crianças com fissuras e 27 mulheres afetadas). Todas as mulheres realizaram dosagens bioquímicas (B12, folato sérico e eritrocitário, hematócrito, hemoglobina e homocisteína). Foi realizada extração de DNA destas mulheres e seus familiares, assim como de trios adicionais (mãe, pai e filho) num total de 428 indivíduos de 231 famílias. 28 polimorfismos de 14 genes da rota metabólica de folato foram genotipados usando TaqMan (Applied Biosystems) ou reação em cadeia de polimerase (PCR). Resultados: Não foi encontrada associação entre os dados bioquímicos nos dois grupos de mulheres (afetadas e não afetadas). O teste de desequilíbrio de transmissão (TDT) revelou significância para os seguintes polimorfismos nos genes BHMTrs651852 (p=0.04), MTRRrs1532268 (p=0.04) e NNMTrs694539 (p=0.03). A interação gene-gene demonstrou significância entre MTRRrs1532268 versus MTRrs10925235 (p=0.03), MTRRrs1532268 versus MTRRrs1801394 (p=0.003), MTRRrs1532268 versus NNMTrs2852447 (p=0.008), NNMTrs694539 versus DHFRrs1643638 (p=<0.0001), NNMTrs694539 versus SHMT1rs921986 (p=0.0001), NNMTrs694539 versus SHMT1rs2168781 (p=0.03). Conclusão: Polimorfismos em genes envolvendo o metabolismo do ácido fólico podem contribuir para a ocorrência de FL/P. Os genes BHMT, MTRR e NNMT mostraram associação com FL/P. Este estudo foi o primeiro a encontrar associação entre o gene NNMT e fissuras orais. Estes achados, portando, devem ser confirmados por estudos adicionais. Estes dados são importantes para o entendimento dos fatores que predispõem às FL/P, e para ser realizada de maneira mais adequada e individualizada a prevenção desta anomalia congênita com ácido fólico. / Introduction: Cleft lip and/or palate (CL/P) are common congenital anomalies with prevalence of 1/700 live births affecting different ethnic groups and social economic status. CL/P has a complex inheritance involving environmental and genetic factors. Among the environmental factors, deficiency of vitamins were reported and several studies have suggested that the use of periconcepcional folic acid might prevent oral clefts. Objective: The aim of this study is to evaluate the biochemical and polymorphisms in genes of the folic acid pathway in non-syndromic CL/P. Methods: 140 women were included, (113) unaffected mothers with CL/P children and 27 affected women. In all women a biochemical measurement (B12, serum folate and eritrocyte, hematocrit, hemoglobin and homocysteine) was performed. We also had DNA extraction of these women and their families, as well as additional trio of (mother, father and son) in a total of 428 individuals of 231 unrelated families. 28 polymorphisms of 14 genes of the folate pathway were genotyped using the TaqMan (Applied Biosystem) or Polymerase Chain Reaction (PCR). Results: Among the biochemical data in the two groups of women (affected and unaffected with cleft lip children) no association was found. The transmission desequilibrium test (TDT) has showed significance for the following polymorphisms in the genes such as BHMTrs651852 (p=0.04), MTRRrs1532268 (p=0.04) and NNMTrs694539 (p=0.03). The gene-gene interaction has showed significance between MTRRrs1532268 versus MTRrs10925235 (p=0.03), MTRRrs1532268 versus NNMTrs2852447 (p=0.008), NNMTrs694539 versus DHFRrs1643638 (p=<0.0001), NNMTrs694539 versus SHMT1rs921986 (p=0.0001), NNMTrs694539 versus SHMT1rs2168781 (p=0.03). Conclusion: Polymorphisms in genes involving the folic acid metabolism might contribute to the occurrence of CL/P. The genes BHMT, MTRR and NNMT have showed association with CL/P. This was the first study to find association between the NNMT and oral clefts. Thus, additional studies are important to these results. These data are important to understand the causes of CL/P as well as to prevent this congenital anomaly with folic acid.
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Zastoupení vybraných mastných kyselin v mléčném tuku dojnic a koz / Composition of selected fatty acids in milk fat of cows and goatsKALA, Robert January 2014 (has links)
Milk fat is the recipient of numerous functions. It affects the biological, chemical, sensory and technological properties of milk. The Czech Republic is consumed and processed, especially cows, goats and ewes milk. The aim was to focus on the description of selected fatty acids in milk fat of dairy cows and goats because of their importance to human health and the factors that influence their composition. The results show that the content of short-chain fatty acids was compared to dairy cows higher in goat breeds. It was also found that the proportion of saturated fatty acids was influenced mainly breed and individuality, while the composition of unsaturated fatty acids was affected more nutrition and feeding. The work describes the biological factors such as breed, individuality, parity and stage of lactation, of the external factors described nutrition and feeding. Chapter biological factors mainly deals with the influence of genetics and contains a description of selected candidate genes affecting milk fat and fatty acids.
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Mineração de genes em regiões genômicas bovinas associadas à resistência ao carrapato Rhipicephalus (Boophilus) microplusCatoia, Vitor 13 August 2014 (has links)
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Previous issue date: 2014-08-13 / The Brazilian cattle industry is presented as highlighted on the world stage and the significant participation of this productive sector in the economy means that there is concern with production losses, among which stands out those caused by infestation of Rhipicephalus (Boophilus) microplus, main ectoparasite vector cattle and various diseases. The genetic variability for resistance to the cattle tick shows that this trait can be genetically improved. For the execution of this work, it was used a study of genome wide association (GWAS) for resistance to Rhipicephalus (Boophilus) microplus, performed by Dr. Fernando Flores Cardoso, with 260 Hereford and 500 Braford animals. The monitoring of the infestation was accomplished by counting tick females larger than 4.5 mm from one of the animal's body side, and the degree of infestation was evaluated for each animal by averaging at least two consecutive counts, with intervals of approximately thirty days, in the months of highest incidence of the parasite. The animals were genotyped using a 50K SNP chip, and it was found a total of 37,346 SNPs that passed in quality test. Among these markers, 178 showed significant effects and allowed the mining of 175 genes in these regions, at an interval of 200 Kb (100 Kb for each side of each marker). Most of these polymorphisms associated with the trait is located in regions without defined functions (intronic and intergenic), and only one of them is located in the splicing region. The most significant regions of the GWAS were identified on chromosomes 7, 21 and 23, which were found 72 genes in linkage disequilibrium with the molecular markers. Therefore, a functional annotation of the genes on these 3 chromosomes was performed, allowing the choice of 11 candidate genes for the study of various metabolic pathways in which they are inserted. Among these pathways, the most important are those related to immune responses, secretion and intracellular transport, calcium influx and epidermal growth and differentiation. / A bovinocultura brasileira apresenta-se como destaque no cenário mundial e a expressiva participação deste setor produtivo na economia faz com que haja preocupação com as perdas produtivas, dentre as quais destaca-se aquelas causadas pela infestação do carrapato Rhipicephalus (Boophilus) microplus, principal ectoparasita de bovinos e vetor de diversas doenças. A variabilidade genética observada para a resistência dos bovinos ao carrapato permite que essa característica seja melhorada geneticamente, como forma alternativa de controle desses ectoparasitos. Para a execução do presente trabalho, foi utilizado um estudo de associação genômica ampla (GWAS) para a resistência ao carrapato R. microplus, o qual foi realizado pela equipe do Dr. Fernando Flores Cardoso (Embrapa Pecuária Sul), com 260 animais da raça Hereford e 500 animais da raça Braford. O monitoramento das infestações foi realizado por meio da contagem de fêmeas do carrapato com tamanho superior a 4,5 mm em um dos lados do corpo do animal, e o grau de infestação de cada animal foi avaliado pela média de pelo menos duas contagens consecutivas, com intervalos de aproximadamente trinta dias, conduzidas no sobreano, nos meses de maior incidência do parasito. Os animais foram genotipados com utilização de um chip de SNPs de 50 K e, após a realização do GWAS, verificou-se que um total de 37.346 SNPs passou nos teste de qualidade. Dentre esses marcadores, 178 SNPs apresentaram efeitos significativos e permitiram a mineração de 175 genes nessas regiões, em um intervalo de 200 Kb (100 Kb para cada lado de cada marcador). A maioria dos polimorfismos associados com a característica está localizada em regiões sem funções determinadas (intergênicas e intrônicas), apenas um deles encontra-se em região de splicing. Sendo assim, estes marcadores podem constituir mutações não causais que se encontram em desequilíbrio de ligação com mutações funcionais. As regiões mais significativas do GWAS foram identificadas nos cromossomos 7, 21 e 23, onde foram identificados 72 genes em desequilíbrio de ligação com os marcadores moleculares. Portanto, foi realizada uma anotação funcional dos genes localizados nesses 3 cromossomos, o que permitiu a seleção de 11 genes candidatos para um estudo mais aprofundado das vias metabólicas nas quais eles estão inseridos. Verificou-se que esses genes participam de processos importantes em vias já relacionadas com a resistência a carrapatos, tais como apresentação de antígenos, transporte e secreção intracelular e diferenciação da epiderme.
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Correlação bioquímica e genes da rota do folato em fissuras oraisPitt, Silvia Brustolin January 2009 (has links)
Introdução: As fissuras de lábio e/ou palato (FL/P) são malformações congênitas comuns na espécie humana, apresentando prevalência de 1/700 recém nascidos vivos, variando de acordo com os diferentes grupos étnicos e fatores sócio-econômicos. As FL/P apresentam padrão complexo de herança, estando envolvidos fatores genéticos e ambientais. Entre os fatores ambientais deficiências de vitaminas já foram descritas, e diversos estudos sugerem que o uso de ácido fólico periconcepcional pode prevenir a recorrência das fissuras orais. Objetivos: Estudar características bioquímicas e polimorfismos em genes da rota metabólica do folato em FL/P não sindrômicas (NS). Métodos: Foram incluídas 140 mulheres (113 mães não afetadas de crianças com fissuras e 27 mulheres afetadas). Todas as mulheres realizaram dosagens bioquímicas (B12, folato sérico e eritrocitário, hematócrito, hemoglobina e homocisteína). Foi realizada extração de DNA destas mulheres e seus familiares, assim como de trios adicionais (mãe, pai e filho) num total de 428 indivíduos de 231 famílias. 28 polimorfismos de 14 genes da rota metabólica de folato foram genotipados usando TaqMan (Applied Biosystems) ou reação em cadeia de polimerase (PCR). Resultados: Não foi encontrada associação entre os dados bioquímicos nos dois grupos de mulheres (afetadas e não afetadas). O teste de desequilíbrio de transmissão (TDT) revelou significância para os seguintes polimorfismos nos genes BHMTrs651852 (p=0.04), MTRRrs1532268 (p=0.04) e NNMTrs694539 (p=0.03). A interação gene-gene demonstrou significância entre MTRRrs1532268 versus MTRrs10925235 (p=0.03), MTRRrs1532268 versus MTRRrs1801394 (p=0.003), MTRRrs1532268 versus NNMTrs2852447 (p=0.008), NNMTrs694539 versus DHFRrs1643638 (p=<0.0001), NNMTrs694539 versus SHMT1rs921986 (p=0.0001), NNMTrs694539 versus SHMT1rs2168781 (p=0.03). Conclusão: Polimorfismos em genes envolvendo o metabolismo do ácido fólico podem contribuir para a ocorrência de FL/P. Os genes BHMT, MTRR e NNMT mostraram associação com FL/P. Este estudo foi o primeiro a encontrar associação entre o gene NNMT e fissuras orais. Estes achados, portando, devem ser confirmados por estudos adicionais. Estes dados são importantes para o entendimento dos fatores que predispõem às FL/P, e para ser realizada de maneira mais adequada e individualizada a prevenção desta anomalia congênita com ácido fólico. / Introduction: Cleft lip and/or palate (CL/P) are common congenital anomalies with prevalence of 1/700 live births affecting different ethnic groups and social economic status. CL/P has a complex inheritance involving environmental and genetic factors. Among the environmental factors, deficiency of vitamins were reported and several studies have suggested that the use of periconcepcional folic acid might prevent oral clefts. Objective: The aim of this study is to evaluate the biochemical and polymorphisms in genes of the folic acid pathway in non-syndromic CL/P. Methods: 140 women were included, (113) unaffected mothers with CL/P children and 27 affected women. In all women a biochemical measurement (B12, serum folate and eritrocyte, hematocrit, hemoglobin and homocysteine) was performed. We also had DNA extraction of these women and their families, as well as additional trio of (mother, father and son) in a total of 428 individuals of 231 unrelated families. 28 polymorphisms of 14 genes of the folate pathway were genotyped using the TaqMan (Applied Biosystem) or Polymerase Chain Reaction (PCR). Results: Among the biochemical data in the two groups of women (affected and unaffected with cleft lip children) no association was found. The transmission desequilibrium test (TDT) has showed significance for the following polymorphisms in the genes such as BHMTrs651852 (p=0.04), MTRRrs1532268 (p=0.04) and NNMTrs694539 (p=0.03). The gene-gene interaction has showed significance between MTRRrs1532268 versus MTRrs10925235 (p=0.03), MTRRrs1532268 versus NNMTrs2852447 (p=0.008), NNMTrs694539 versus DHFRrs1643638 (p=<0.0001), NNMTrs694539 versus SHMT1rs921986 (p=0.0001), NNMTrs694539 versus SHMT1rs2168781 (p=0.03). Conclusion: Polymorphisms in genes involving the folic acid metabolism might contribute to the occurrence of CL/P. The genes BHMT, MTRR and NNMT have showed association with CL/P. This was the first study to find association between the NNMT and oral clefts. Thus, additional studies are important to these results. These data are important to understand the causes of CL/P as well as to prevent this congenital anomaly with folic acid.
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Correlação bioquímica e genes da rota do folato em fissuras oraisPitt, Silvia Brustolin January 2009 (has links)
Introdução: As fissuras de lábio e/ou palato (FL/P) são malformações congênitas comuns na espécie humana, apresentando prevalência de 1/700 recém nascidos vivos, variando de acordo com os diferentes grupos étnicos e fatores sócio-econômicos. As FL/P apresentam padrão complexo de herança, estando envolvidos fatores genéticos e ambientais. Entre os fatores ambientais deficiências de vitaminas já foram descritas, e diversos estudos sugerem que o uso de ácido fólico periconcepcional pode prevenir a recorrência das fissuras orais. Objetivos: Estudar características bioquímicas e polimorfismos em genes da rota metabólica do folato em FL/P não sindrômicas (NS). Métodos: Foram incluídas 140 mulheres (113 mães não afetadas de crianças com fissuras e 27 mulheres afetadas). Todas as mulheres realizaram dosagens bioquímicas (B12, folato sérico e eritrocitário, hematócrito, hemoglobina e homocisteína). Foi realizada extração de DNA destas mulheres e seus familiares, assim como de trios adicionais (mãe, pai e filho) num total de 428 indivíduos de 231 famílias. 28 polimorfismos de 14 genes da rota metabólica de folato foram genotipados usando TaqMan (Applied Biosystems) ou reação em cadeia de polimerase (PCR). Resultados: Não foi encontrada associação entre os dados bioquímicos nos dois grupos de mulheres (afetadas e não afetadas). O teste de desequilíbrio de transmissão (TDT) revelou significância para os seguintes polimorfismos nos genes BHMTrs651852 (p=0.04), MTRRrs1532268 (p=0.04) e NNMTrs694539 (p=0.03). A interação gene-gene demonstrou significância entre MTRRrs1532268 versus MTRrs10925235 (p=0.03), MTRRrs1532268 versus MTRRrs1801394 (p=0.003), MTRRrs1532268 versus NNMTrs2852447 (p=0.008), NNMTrs694539 versus DHFRrs1643638 (p=<0.0001), NNMTrs694539 versus SHMT1rs921986 (p=0.0001), NNMTrs694539 versus SHMT1rs2168781 (p=0.03). Conclusão: Polimorfismos em genes envolvendo o metabolismo do ácido fólico podem contribuir para a ocorrência de FL/P. Os genes BHMT, MTRR e NNMT mostraram associação com FL/P. Este estudo foi o primeiro a encontrar associação entre o gene NNMT e fissuras orais. Estes achados, portando, devem ser confirmados por estudos adicionais. Estes dados são importantes para o entendimento dos fatores que predispõem às FL/P, e para ser realizada de maneira mais adequada e individualizada a prevenção desta anomalia congênita com ácido fólico. / Introduction: Cleft lip and/or palate (CL/P) are common congenital anomalies with prevalence of 1/700 live births affecting different ethnic groups and social economic status. CL/P has a complex inheritance involving environmental and genetic factors. Among the environmental factors, deficiency of vitamins were reported and several studies have suggested that the use of periconcepcional folic acid might prevent oral clefts. Objective: The aim of this study is to evaluate the biochemical and polymorphisms in genes of the folic acid pathway in non-syndromic CL/P. Methods: 140 women were included, (113) unaffected mothers with CL/P children and 27 affected women. In all women a biochemical measurement (B12, serum folate and eritrocyte, hematocrit, hemoglobin and homocysteine) was performed. We also had DNA extraction of these women and their families, as well as additional trio of (mother, father and son) in a total of 428 individuals of 231 unrelated families. 28 polymorphisms of 14 genes of the folate pathway were genotyped using the TaqMan (Applied Biosystem) or Polymerase Chain Reaction (PCR). Results: Among the biochemical data in the two groups of women (affected and unaffected with cleft lip children) no association was found. The transmission desequilibrium test (TDT) has showed significance for the following polymorphisms in the genes such as BHMTrs651852 (p=0.04), MTRRrs1532268 (p=0.04) and NNMTrs694539 (p=0.03). The gene-gene interaction has showed significance between MTRRrs1532268 versus MTRrs10925235 (p=0.03), MTRRrs1532268 versus NNMTrs2852447 (p=0.008), NNMTrs694539 versus DHFRrs1643638 (p=<0.0001), NNMTrs694539 versus SHMT1rs921986 (p=0.0001), NNMTrs694539 versus SHMT1rs2168781 (p=0.03). Conclusion: Polymorphisms in genes involving the folic acid metabolism might contribute to the occurrence of CL/P. The genes BHMT, MTRR and NNMT have showed association with CL/P. This was the first study to find association between the NNMT and oral clefts. Thus, additional studies are important to these results. These data are important to understand the causes of CL/P as well as to prevent this congenital anomaly with folic acid.
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Cartografiado de QTL y genes candidatos asociados a metabolitos determinantes de la calidad de fruto en melocotónSánchez, Gerardo 16 December 2013 (has links)
Tradicionalmente los programas de mejora del melocotón (Prunus persica (L.) Batsch) se centraron fundamentalmente en la obtención de genotipos elite de alta productividad, resistentes a plagas y patógenos, adaptados a diferentes zonas agroecológicas y que produzcan frutos de gran tamaño y buen aspecto. Como resultado, muchos de estos programas han obtenido cultivares de excelentes características agronómicas. No obstante, el mejoramiento selectivo hacia caracteres agronómicos puede ir en detrimento de la calidad organoléptica del fruto como fue demostrado en el caso de fresa y tomate donde algunos aromas se perdieron en el proceso de mejora (Klee and Giovannoni, 2011; Olbricht et al., 2008). En melocotón, la disminución de la calidad del fruto ha sido percibida por los consumidores y además es la mayor causa de insatisfacción de los mismos (Bruhn et al., 1991). Un probable consecuencia de esto puede ser el bajo consumo de melocotón en comparación con otras frutas como el plátano y la manzana (Crisosto, 2006). Estudios pioneros han establecido que el aroma es uno de los atributos principales por los cuales los consumidores juzgan la calidad del melocotón (Bruhn, 1995). El aroma está definido íntegramente por los compuestos volátiles orgánicos (VOCs) los cuales también contribuyen al sabor del fruto en combinación con azucares y ácidos orgánicos. Los volátiles del melocotón han sido estudiados con anterioridad, describiéndose un poco más de 100 compuestos incluyendo: lactonas, esteres, terpenos, aldehídos, ácidos carboxílicos y alcoholes entre otros [(Aubert and Milhet, 2007) y referencias incluidas]. La identificación de regiones génicas y genes candidatos para el control de los aromas del fruto resulta un punto fundamental para su posterior implementación en programas de mejora con el fin de obtener melocotones de mayor calidad. En este sentido nos propusimos la identificación de QTLs (del inglés ``Quantitative trait loci'') y genes candidatos involucrados en la producción de los compuestos volátiles del melocotón.
El desarrollo reciente de un conjunto técnicas analíticas de mayor potencia permitió el advenimiento de una nueva plataforma tecnológica, la metabolómica, que contempla el análisis global de los metabolitos de un organismo permitiendo abordar la evaluación de calidad de una forma más exhaustiva. Dentro de ellas, la tecnología HS-SPME-GC-MS (del inglés ``Head Space-Solid Phase Microextraction-Gas Chromatography-Mass Spectroscopy'') es actualmente el método de elección para el análisis de volátiles debido a su alta sensibilidad, reproducibilidad y robustez (Tikunov et al., 2005). Además el análisis en conjunto de los datos derivados de la metabolómica con otras tecnologías de alto rendimiento para el análisis de expresión de genes, como lo son los microarrays, ha permitido el descubrimiento de genes implicados la producción de diversos metabolitos en Arabidopsis y tomate (Mounet et al., 2009; Saito and Matsuda, 2010; Carrera et al. 2012).
En una primera instancia nos propusimos el desarrollo de una plataforma de alto rendimiento basada en HS-SPME-GC-MS para la identificación y cuantificación de compuestos volátiles en fruto de melocotón. Se ensayarán diferentes protocolos para la extracción de los compuestos volátiles con el fin de identificar el más adecuado (es decir el más sensible manteniendo la reproducibilidad y con una robustez satisfactoria). Una vez desarrollado un protocolo adecuado se analizará en paralelo la evolución de los compuestos volátiles y la expresión de genes mediante microarrays durante la maduración de diferentes genotipos de melocotón con el objetivo de identificar patrones comunes de co-regulación entre metabolitos y genes durante el desarrollo del fruto. Por último, se propuso la identificación de regiones génicas implicadas en la producción de volátiles mediante análisis de QTLs. / Sánchez, G. (2013). Cartografiado de QTL y genes candidatos asociados a metabolitos determinantes de la calidad de fruto en melocotón [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/34511 / TESIS
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Applying machine learning methods for genomic analysis of reproductive traits in Nellore cattle /Alves, Anderson Antonio Carvalho January 2019 (has links)
Orientador: Lucia Galvão de Albuquerque / Resumo: A seleção de animais geneticamente superiores com base na informação genômica tem sido uma tendência crescente e promissora em programas de melhoramento. No entanto, os principais métodos de predição genômica envolvem modelos paramétricos, que em sua maioria, assumem somente variância aditiva para o efeito dos marcadores, ignorando-se possíveis relações não-lineares. A consideração de tais efeitos pode ser importante para melhorar a habilidade de predição em características com arquitetura genética complexa. Recentemente, tem crescido o interesse em métodos de predição semi e não paramétricos. Dentro desse contexto, os métodos de aprendizagem de máquina tais como Redes Neurais Artificiais (ANN), “Random Forest” (RF) e “Support Vector Machines” (SVM) são alternativas interessantes. Os objetivos do presente estudo foram: i) Comparar o desempenho preditivo do modelo “Genomic Best Linear Unbiased Predictor” (GBLUP) e de métodos de aprendizagem de máquina em populações simuladas de bovinos de corte, apresentando diferentes níveis para efeitos de dominância; ii) Investigar a habilidade de predição de diferentes métodos de aprendizagem de máquina para predição genômica de características reprodutivas em bovinos da raça Nelore; iii) Desenvolver um estudo de associação genômica ampla (GWAS) utilizando a metodologia “Random Forest”, a fim de buscar genes candidatos para idade ao primeiro parto em novilhas da raça Nelore. No primeiro estudo, o genoma simulado compreendeu um painel de SN... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The selection of genetically superior animals based on genomic information has been an increasing and promising trend in breeding programs. However, the main methods used for genome-enabled prediction involve parametric models that mostly assume only additive variance for markers effects, ignoring possible nonlinear relationships. Accounting for such effects may be important to improve the predictive ability for traits with complex genetic architecture. The interest in semi and non-parametric prediction methods has recently increased. Within this context, machine learning methods such as Artificial Neural Networks (ANN), Random Forest (RF) and Support Vector Machines (SVM) are an interesting alternative. The aims of the present study were: i) To compare the predictive performance of Genomic Best Linear Unbiased Predictor (GBLUP) and machine learning methods in simulated beef cattle populations presenting different degrees of dominance; ii) To investigate the predictive ability of different machine learning for genome-enabled prediction of reproductive traits in Nellore cattle and compare their performance with parametric approaches (GBLUP and BLASSO); iii) To perform a genome-wide association study (GWAS) using the Random Forest approach for scanning candidate genes for age at first calving in Nellore heifers. In the first study, the simulated genome comprised 50k single nucleotide polymorphisms (SNPs) and 300 QTL (Quantitative Trait Loci), both biallelic and randomly distrib... (Complete abstract click electronic access below) / Doutor
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The Identification of Colorectal Cancer Susceptibility Genes Using a Cross-Species, Systems Genetics ApproachGerber, Madelyn Margaret 19 May 2015 (has links)
No description available.
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GENOME WIDE ASSOCIATION STUDIES TO IDENTIFY GENES FOR RESISTANCE TO FUSARIUM EAR ROT IN MAIZESTAGNATI, LORENZO 31 May 2017 (has links)
Fusarium verticillioides è l’agente responsabile della Fusariosi della Spiga del mais, contamina la granella con fumonisine, micotossine responsabili di diverse patologie umane e animali.
Per la resistenza alla fusariosi e all’accumulo di fumonisine esiste variabilità tra genotipi diversi ma non sono ancora disponibili ibridi immuni.
L’obiettivo di questo lavoro è stato quello di individuare marcatori associati alla resistenza a F. verticillioides.
Mediante un bioassay è stato testato un association panel per la resistenza a F. verticillioides.
Al fine di identificare i marcatori di resistenza sono stati applicati un approccio GWAS e uno per geni candidati.
L’analisi GWAS è stata eseguita con 227K SNPs restituendo 206 marcatori significativi.
Da un lavoro di RNASequencing sono stati individuati i geni coinvolti nella risposta a F. verticillioides mentre i geni R sono stati recuperati della letteratura scientifica.
Genotipi resistenti (CO433 e CO441) e suscettibili (CO354 e CO389) sono stati scelti per individuare polimorfismi nei geni candidati da associare ai fenotipi rilevati mediante il bioassay. Quattro marcatori sono risultati significativi.
Infine, la correlazione tra l’incidenza della fusariosi rilevata in campo e mediante bioassay è stata analizzata in una popolazione di 172 RIL derivanti da CO441 x CO354, tuttavia, non è stata individuata alcuna corrispondenza. / Fusarium verticillioides is the causal agent of Fusarium ear rot (FER) in maize and contaminates grains with fumonisin, a family of mycotoxins involved in several human and animal diseases. Quantitative genetic variation exists for resistance to FER and fumonisin contamination among genotypes, however, resistant maize hybrids are currently not available.
The aim of this work was the identification of genetic markers associated to resistance against F. verticillioides.
A bioassay was used to screen inbred lines of the maize association population for FER resistance, GWAS and candidate gene approaches were applied to identify markers.
GWAS was performed using a 227K SNP matrix and resulting in 206 significant markers.
Genes involved in F. verticillioides response in developing maize kernels were retrieved from a previous RNASequencing study while maize R genes were retrieved from scientific literature. Resistant (CO433 and CO441) and susceptible genotypes (CO389 and CO354) were selected to amplify and sequence candidate genes. Polymorphisms detected were used to find association with phenotypes scored using the bioassay. Four significant markers were found.
Finally, the correlation between FER phenotypes scored in field experiments and bioassay phenotypes was investigated. A population of 172 RILs (CO441 x CO354), was tested. No correlation was found.
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