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A fluorose dentária é uma patologia que ocorre durante a formação dos dentes na presença de doses excessivas de fluoreto (F-). Os mecanismos pelos quais o F provoca a fluorose ainda são poucos conhecidos. A influência de fatores genéticos tem sido considerada na suscetibilidade/resistência do indivíduo em desenvolver a fluorose. Duas linhagens de camundongos (A/J e 129P3/J) com diferença na resistência ou suscetibilidade à fluorose dentária foram utilizadas para determinar se a suscetibilidade à fluorose pode ser explicada pela diferença no metabolismo e se há diferença no perfil protéico dos rins e urina destes animais. Para isso, um estudo metabólico foi conduzido com 18 camundongos A/J (suscetível) e 18 129P3 / J (resistente) após o desmame. Cada amostra foi dividida em 3 grupos, com diferentes concentrações de F- na água de beber (0, 10 e 50 ppm F). Uma vez que um estudo piloto revelou que os camundongos A/J ingeriam um maior volume de água quando comparado com o 129P3/J, a concentração de F- na água dada aos camundongos A/J foi ajustada semanalmente a fim de fornecer doses semelhantes de F- para ambas linhagens. Os animais foram mantidos em gaiolas metabólicas (n = 2/gaiola) por 7 semanas, com livre acesso à água e dieta de baixa ingestão de F- (0,95 ppm). A ingestão e excreção de F- foram calculadas, bem como os níveis de F- no plasma, no fêmur e no rim. O grau de fluorose dentária foi avaliado usando análise de fluorescência quantitativa (QLF) e exame clínico. Os perfis proteômicos renal e urinário foram examinados utilizando 2D-PAGE e coloração com azul de Coomassie.. Os dados do estudo metabólico foram testados para diferenças significativas pela ANOVA a 2 critérios (p <0,05). As imagens dos géis e as diferenças estatísticas (ANOVA, p<0,05) foram analisadas pelo programa Image Master Platinum 7.0. Os camundongos da linhagem A/J submetidos à alta concentração de fluoreto apresentaram um grau de fluorose significativamente maior quando comparado com a linhagem 129P3/J. A ingestão total de F- não diferiu significativamente entre as linhagens. A excreção total de F- foi significativamente maior para os camundongos A/J, devido à maior excreção urinária de F-. As duas linhagens não diferiram em relação à absorção F-, mas os animais 129P3/J retiveram significativamente maiores quantidades de F-, que foi consistente com níveis mais elevados de F- no fêmur, no entanto, os níveis de F- no plasma não diferiram significativamente entre as linhagens. Para os rins, a análise quantitativa de intensidade detectou, entre as linhagens A/J e 129P3/J, 122, 126 e 134 spots diferencialmente expressos nos grupos controle, e que receberam baixa e alta concentração de F-, respectivamente. Para a urina, 84 spots diferencialmente expressos foram observados para o grupo controle, 68 para o grupo que recebeu baixa concentração de F- e 66 para o grupo que recebeu alta concentração de F-. Os dados mostraram que há diferenças metabólicas e no perfil de expressão protéica renal e urinária intrínsecas a estas linhagens e que a exposição ao F- é capaz de alterar estes padrões. / Dental fluorosis occurs during tooth formation when excessive doses of fluoride (F) are ingested. The mechanisms that underlie the pathogenesis of dental fluorosis are not known so far. The influence of genetic factors has been considered in individual susceptibility/resistance to develop fluorosis. Two inbred mice strains (A/J and 129P3/J) have been reported to have different susceptibilities to dental fluorosis. They were used in the present study to determine if the susceptibility to dental fluorosis can be explained by alterations in F metabolism and to evaluate if there is difference in the profile of protein expression in kidney and urine of these animals. For this, a metabolic study was conducted with 18 A/J (susceptible) and 18 129P3/J (resistant) weanling mice. Each strain was divided into 3 groups, with differed according to the F concentration given in the drinking water (0, 10 and 50 ppm F). Since a pilot study showed that the A/J mice drank a higher volume of water when compared with the 129P3/J, the F concentration in the water given to the A/J mice was weekly adjusted in order to provide similar F intakes for both strains. The mice were housed in metabolic cages (n=2/cage) for 7 weeks, with free access to water and low-F diet (0.95 ppm). F intake and excretion were calculated, as well as plasma, femur and kidney F levels. The degree of dental fluorosis was assessed using QLF and clinical examination. Renal and urinary proteome profiles were examined using 2D-PAGE and coomassie brilliant blue staining. Data were tested for significant differences by 2-way repeated-measures ANOVA (p<0.05). The gels images and statistical differences (ANOVA, p <0.05) were analyzed by the Image Master Platinum 7.0 software. Significantly higher QLF scores were observed for the A/J mice submitted to 50 ppm F. The total F intake did not significantly differ between the strains. The total F excretion was significantly higher for the A/J mice, due to the higher urinary F excretion. The two strains did not differ in respect to F absorption, but the 129P3/J mice retained significantly higher amounts of F, which was consistent with their higher femur F levels. Plasma F levels, however, did not significantly differ between the strains. For kidney, quantitative intensity analysis detected, between strains A/J and 129P3/J, 122, 126 e 134 spots differentially expressed in the control group, in the group receiving low and high F concentrations, respectively. For urine, 84 spots differentially expressed were detected for control group, 68 for the group receiving low F concentration and 66 for the group receiving high F concentration. Data showed that intrinsic differences occur in the metabolism of F and profile of protein expression between these strains and that these profiles can be altered in the presence of F.

A obesidade comum, determinada por mecanismo de herança multifatorial, é atualmente um dos problemas mais importantes de saúde publica no mundo. Estudos de associação entre polimorfismos em genes candidatos e a predisposição à obesidade têm sido realizados em diferentes populações a fim de tentar esclarecer as bases genéticas que controlam o acúmulo de gordura corporal. Esse trabalho teve por objetivo principal estudar a associação dos polimorfismos LEP A19G, LEPR Gln223Arg, ADRB2 Arg16Gly, PPARG Pro12Ala, PLIN 6209T>C, RETN -420C>G e INSIG2 rs7566605 a medidas antropométricas relacionadas ao fenótipo de obesidade, tais como Índice de Massa Corporal (IMC), Circunferência da Cintura (Cc) e Razão Cintura/Quadril (RCQ) em populações afrodescendentes de remanescentes de quilombos, localizadas no Vale do Ribeira-SP. Além disso, procuramos identificar os principais fatores ambientais que influenciam o acúmulo de gordura corporal nessas populações. Nossa amostra constituiu-se de cerca de 790 indivíduos genotipados em relação a esses sete polimorfismos dos quais foram coletadas medidas de peso, altura, circunferências da cintura e do quadril, pregas cutâneas tricipital e subescapular e informações sobre o seu Grau de Atividade Física (GAF), tabagismo e consumo de álcool. Para os estudos de associação, os indivíduos foram analisados de duas formas distintas: como indivíduos independentes e agrupados em 53 genealogias. As metodologias de estudo casocontrole, comparação entre os valores das medianas entre indivíduos com diferentes genótipos e análises de regressão linear e logística foram empregadas quando estudamos os indivíduos de forma independente. Testes de estratificação populacional, associação total e associação dentro das famílias, utilizando pares de irmãos, foram realizados por meio do pacote computacional QTDT (Quantitative Transmission Disequilibrium Test). Nossos resultados indicaram uma maior freqüência de indivíduos com sobrepeso (IMC>=25 Kg/m2) e obesos (IMC>=30 Kg/m2) entre as mulheres (52% e 17,5%, respectivamente) do que entre os homens (17,5% e 2,75%, respectivamente), devido provavelmente à diferença em relação ao GAF, que é maior no grupo dos homens. Apesar de o GAF estar relacionado às diferenças observadas entre homens e mulheres em relação ao IMC, ele não explica as diferenças encontradas em relação ao IMC, Cc e RCQ entre indivíduos do mesmo sexo. Análises de regressão indicaram que os parâmetros não-genéticos que parecem melhor explicar as variações do IMC são o sexo e o tabagismo; da Cc são o sexo, a idade e o tabagismo e da RCQ, a idade e o sexo. Análises de regressão logística indicaram que entre as mulheres, o aumento do risco de apresentar fenótipos de sobrepeso, medidos por meio do IMC, Cc e RCQ, está relacionado ao fato de não fumar, consumir bebida alcoólica e ter maior idade. As análises de associação indicaram que nessas populações o alelo Gln do polimorfismo LEPR Gln23Arg está associado a valores maiores de IMC nas mulheres e RCQ nos homens, conforme apontaram as análises caso-controle, de comparação entre medianas e regressões linear e logística. O alelo Arg do polimorfismo ADRB2 Arg16Gly está associado a valores maiores de Cc e RCQ apenas entre os homens, conforme indicaram as análises de comparação entre as medianas e regressão linear. O alelo Ala do polimorfismo PPARG Pro12Ala está associado a valores maiores de IMC, Cc e RCQ nas mulheres, conforme apontaram as análises caso-controle, de comparação entre medianas e regressão linear. O alelo A do polimorfismo PLIN 6209T>C está associado a valores maiores de IMC e Cc entre as mulheres e a valores maiores de IMC, Cc e RCQ entre os homens, conforme indicaram os resultados obtidos com a análise de comparação entre medianas, regressão linear e regressão logística. Apenas entre as mulheres o alelo G do polimorfismo RETN -420C>G mostrou-se associado a valores mais altos de IMC e Cc de acordo com os resultados obtidos com a comparação entre medianas e com a regressão logística. Os resultados obtidos com as análises caso-controle e de comparação entre medianas indicaram que o alelo C do polimorfismo INSIG2 rs7566605 está associado a valores maiores de Cc nas mulheres e IMC nos homens. O único resultado positivo de associação detectado por meio da análise de pares de irmãos refere-se ao polimorfismo LEP A19G e o IMC, sendo o alelo G o que está associado aos valores maiores em ambos os sexos. Em resumo, nossos resultados sugerem a participação dos genótipos nos genes LEP, LEPR, ADRB2, PPARG, PLIN, RETN e INSIG2 na predisposição à obesidade nas populações de remanescentes de quilombos do Vale do Ribeira. / Obesity, which is determined by multifactorial inheritance, is currently one of the most important issues concerning public health all over the world. Studies on the association of polymorphisms in genes with a possible role in the susceptibility to obesity have been conducted in different populations in the world, in order to elucidate the genetic basis that control the accumulation of body fat. This work had as the main goal to study the association of the polymorphisms LEP A19G, LEPR Gln223Arg, ADRB2 Arg16Gly, PPARG Pro12Ala, PLIN 6209T>C, RETN -420C>G and INSIG2 rs7566605 to the anthropometrical measurements related to the phenotype of obesity, such as Body Mass Index (BMI), Waist Circumference (WC) and Waist to Hip Ratio (WHR) in african-derived populations from remnants of quilombos, located in Ribeira Valley, in State of São Paulo, Brazil. Furthermore, we sought to identify the main environmental factors that influenced the accumulation of body fat in these populations. Our sample comprises about 790 individuals genotyped in relation to these seven polymorphisms, from which measurements of weight, height, hip and waist circumferences, tricipital and subscapular skinfolds, and information about the Physical Activity Level (PAL), alcohol and tobacco consumption were obtained. For the association studies, the individuals were analyzed in two distinct ways: as independent individuals or grouped in 53 genealogies. The methodologies of case-control study, comparison between the medians among individuals with different genotypes, linear and logistic regression analysis were applied when we studied the individuals in the independent approach. Tests of population stratification, total association and association within the families, using pairs of siblings, were conducted by the computational pack QTDT (Quantitative Transmission Disequilibrium Test). Our results indicated a higher incidence of overweighed (BMI>=25 Kg/m2) and obese individuals (BMI>=30 Kg/m2) among women (52% and 17,5%, respectively) than among men (17,5% and 2,75%, respectively), probably due to the difference in the PAL, which is higher among men. Although the PAL is related to the differences in BMI observed between men and women, it does not explain the differences in relation to the BMI, WC and WHR found among individuals of the same sex. Regression analyses indicated that the non-genetic parameters that better explain the variations of BMI are sex and tobacco consumption; for WC are sex, age and tobacco consumption and for the WHR are age and sex. Logistic regression analyses indicated that among women, the increase in risk of presenting overweight, measured by the BMI, WC and WHR is related to not smoking (BMI, WC), consuming alcohol (BMI) and being elder (WC, WHR). The association analyses indicated that in these populations, the allele Gln of the polymorphism LEPR Gln23Arg is associated to higher values of BMI in women and WHR in men, as the case-control, median comparisons and linear regressions analyses indicated. The allele Ala of the polymorphism PPARG Pro12Ala is associated to higher values of BMI and WC among women and higher values of BMI, WC and WHR among men, according to the results obtained with the median comparison, and linear and logistic regressions analyses. Only among women, the allele G of the polymorphism RETN -420C>G was associated to higher BMI and WC values, as from the analysis of comparison of medians, and logistic regression indicated. The results obtained with the case-control analyses and median comparisons, suggested that the allele C of the polymorphism INSIG2 rs7566605 is associated to higher values of WC in women and BMI in men. The only positive result of association detected by the analysis of pairs of siblings is related to the polymorphism LEP A19G and the BMI. The allele G is associated to higher values of BMI in both sexes. As a summary, our results indicate the participation of the genotypes in genes LEP, LEPR, ADRB2, PPARG, PLIN, RETN and INSIG2 in the susceptibility to obesity in african-derived populations from quilombos in Ribeira River Valley.

The accessibility of high-throughput biology data brought a great deal of attention to disease association studies. High density maps of single nucleotide polymorphism (SNP's) as well as massive genotype data with large number of individuals and number of SNP's become publicly available. By now most analysis of the new data is undertaken by the statistics community. In this dissertation, we pursue a different line of attack on genetic susceptibility to complex disease that adheres to the computer science community with an emphasis on design rather than analytical methodology. The main goal of disease association analysis is to identify gene variations contributing to the risk of and/or susceptibility to a particular disease. There are basically two main steps in susceptibility: (i) haplotyping of the population and (ii) predicting the genetic susceptibility to diseases. Although there exist many phasing methods for step (i), phasing and missing data recovery for data representing family trios is lagging behind, and most disease association studies are based on family trios. This study is devoted to the problem of assessing accumulated information targeting to predict genotype susceptibility to complex diseases with significantly high accuracy and statistical power. The dissertation proposes two new greedy and integer linear programming based solution methods for step (i). We also proposed several universal and ad hoc methods for step (ii). The quality of susceptibility prediction algorithm has been assessed using leave-one-out and leave-many-out tests and shown to be statistically significant based on randomization tests. The prediction of disease status can also be viewed as an integrated risk factor. A combinatorial prediction complexity measure has been proposed for case/control studies. The best prediction rate achieved by the proposed algorithms is 69.5% for Crohn's disease and 61.3% for autoimmune disorder, respectively, which are significantly higher than those achieved by universal prediction methods such as Support Vector Machine (SVM) and known statistic methods.

A obesidade comum, determinada por mecanismo de herança multifatorial, é atualmente um dos problemas mais importantes de saúde publica no mundo. Estudos de associação entre polimorfismos em genes candidatos e a predisposição à obesidade têm sido realizados em diferentes populações a fim de tentar esclarecer as bases genéticas que controlam o acúmulo de gordura corporal. Esse trabalho teve por objetivo principal estudar a associação dos polimorfismos LEP A19G, LEPR Gln223Arg, ADRB2 Arg16Gly, PPARG Pro12Ala, PLIN 6209T>C, RETN -420C>G e INSIG2 rs7566605 a medidas antropométricas relacionadas ao fenótipo de obesidade, tais como Índice de Massa Corporal (IMC), Circunferência da Cintura (Cc) e Razão Cintura/Quadril (RCQ) em populações afrodescendentes de remanescentes de quilombos, localizadas no Vale do Ribeira-SP. Além disso, procuramos identificar os principais fatores ambientais que influenciam o acúmulo de gordura corporal nessas populações. Nossa amostra constituiu-se de cerca de 790 indivíduos genotipados em relação a esses sete polimorfismos dos quais foram coletadas medidas de peso, altura, circunferências da cintura e do quadril, pregas cutâneas tricipital e subescapular e informações sobre o seu Grau de Atividade Física (GAF), tabagismo e consumo de álcool. Para os estudos de associação, os indivíduos foram analisados de duas formas distintas: como indivíduos independentes e agrupados em 53 genealogias. As metodologias de estudo casocontrole, comparação entre os valores das medianas entre indivíduos com diferentes genótipos e análises de regressão linear e logística foram empregadas quando estudamos os indivíduos de forma independente. Testes de estratificação populacional, associação total e associação dentro das famílias, utilizando pares de irmãos, foram realizados por meio do pacote computacional QTDT (Quantitative Transmission Disequilibrium Test). Nossos resultados indicaram uma maior freqüência de indivíduos com sobrepeso (IMC>=25 Kg/m2) e obesos (IMC>=30 Kg/m2) entre as mulheres (52% e 17,5%, respectivamente) do que entre os homens (17,5% e 2,75%, respectivamente), devido provavelmente à diferença em relação ao GAF, que é maior no grupo dos homens. Apesar de o GAF estar relacionado às diferenças observadas entre homens e mulheres em relação ao IMC, ele não explica as diferenças encontradas em relação ao IMC, Cc e RCQ entre indivíduos do mesmo sexo. Análises de regressão indicaram que os parâmetros não-genéticos que parecem melhor explicar as variações do IMC são o sexo e o tabagismo; da Cc são o sexo, a idade e o tabagismo e da RCQ, a idade e o sexo. Análises de regressão logística indicaram que entre as mulheres, o aumento do risco de apresentar fenótipos de sobrepeso, medidos por meio do IMC, Cc e RCQ, está relacionado ao fato de não fumar, consumir bebida alcoólica e ter maior idade. As análises de associação indicaram que nessas populações o alelo Gln do polimorfismo LEPR Gln23Arg está associado a valores maiores de IMC nas mulheres e RCQ nos homens, conforme apontaram as análises caso-controle, de comparação entre medianas e regressões linear e logística. O alelo Arg do polimorfismo ADRB2 Arg16Gly está associado a valores maiores de Cc e RCQ apenas entre os homens, conforme indicaram as análises de comparação entre as medianas e regressão linear. O alelo Ala do polimorfismo PPARG Pro12Ala está associado a valores maiores de IMC, Cc e RCQ nas mulheres, conforme apontaram as análises caso-controle, de comparação entre medianas e regressão linear. O alelo A do polimorfismo PLIN 6209T>C está associado a valores maiores de IMC e Cc entre as mulheres e a valores maiores de IMC, Cc e RCQ entre os homens, conforme indicaram os resultados obtidos com a análise de comparação entre medianas, regressão linear e regressão logística. Apenas entre as mulheres o alelo G do polimorfismo RETN -420C>G mostrou-se associado a valores mais altos de IMC e Cc de acordo com os resultados obtidos com a comparação entre medianas e com a regressão logística. Os resultados obtidos com as análises caso-controle e de comparação entre medianas indicaram que o alelo C do polimorfismo INSIG2 rs7566605 está associado a valores maiores de Cc nas mulheres e IMC nos homens. O único resultado positivo de associação detectado por meio da análise de pares de irmãos refere-se ao polimorfismo LEP A19G e o IMC, sendo o alelo G o que está associado aos valores maiores em ambos os sexos. Em resumo, nossos resultados sugerem a participação dos genótipos nos genes LEP, LEPR, ADRB2, PPARG, PLIN, RETN e INSIG2 na predisposição à obesidade nas populações de remanescentes de quilombos do Vale do Ribeira. / Obesity, which is determined by multifactorial inheritance, is currently one of the most important issues concerning public health all over the world. Studies on the association of polymorphisms in genes with a possible role in the susceptibility to obesity have been conducted in different populations in the world, in order to elucidate the genetic basis that control the accumulation of body fat. This work had as the main goal to study the association of the polymorphisms LEP A19G, LEPR Gln223Arg, ADRB2 Arg16Gly, PPARG Pro12Ala, PLIN 6209T>C, RETN -420C>G and INSIG2 rs7566605 to the anthropometrical measurements related to the phenotype of obesity, such as Body Mass Index (BMI), Waist Circumference (WC) and Waist to Hip Ratio (WHR) in african-derived populations from remnants of quilombos, located in Ribeira Valley, in State of São Paulo, Brazil. Furthermore, we sought to identify the main environmental factors that influenced the accumulation of body fat in these populations. Our sample comprises about 790 individuals genotyped in relation to these seven polymorphisms, from which measurements of weight, height, hip and waist circumferences, tricipital and subscapular skinfolds, and information about the Physical Activity Level (PAL), alcohol and tobacco consumption were obtained. For the association studies, the individuals were analyzed in two distinct ways: as independent individuals or grouped in 53 genealogies. The methodologies of case-control study, comparison between the medians among individuals with different genotypes, linear and logistic regression analysis were applied when we studied the individuals in the independent approach. Tests of population stratification, total association and association within the families, using pairs of siblings, were conducted by the computational pack QTDT (Quantitative Transmission Disequilibrium Test). Our results indicated a higher incidence of overweighed (BMI>=25 Kg/m2) and obese individuals (BMI>=30 Kg/m2) among women (52% and 17,5%, respectively) than among men (17,5% and 2,75%, respectively), probably due to the difference in the PAL, which is higher among men. Although the PAL is related to the differences in BMI observed between men and women, it does not explain the differences in relation to the BMI, WC and WHR found among individuals of the same sex. Regression analyses indicated that the non-genetic parameters that better explain the variations of BMI are sex and tobacco consumption; for WC are sex, age and tobacco consumption and for the WHR are age and sex. Logistic regression analyses indicated that among women, the increase in risk of presenting overweight, measured by the BMI, WC and WHR is related to not smoking (BMI, WC), consuming alcohol (BMI) and being elder (WC, WHR). The association analyses indicated that in these populations, the allele Gln of the polymorphism LEPR Gln23Arg is associated to higher values of BMI in women and WHR in men, as the case-control, median comparisons and linear regressions analyses indicated. The allele Ala of the polymorphism PPARG Pro12Ala is associated to higher values of BMI and WC among women and higher values of BMI, WC and WHR among men, according to the results obtained with the median comparison, and linear and logistic regressions analyses. Only among women, the allele G of the polymorphism RETN -420C>G was associated to higher BMI and WC values, as from the analysis of comparison of medians, and logistic regression indicated. The results obtained with the case-control analyses and median comparisons, suggested that the allele C of the polymorphism INSIG2 rs7566605 is associated to higher values of WC in women and BMI in men. The only positive result of association detected by the analysis of pairs of siblings is related to the polymorphism LEP A19G and the BMI. The allele G is associated to higher values of BMI in both sexes. As a summary, our results indicate the participation of the genotypes in genes LEP, LEPR, ADRB2, PPARG, PLIN, RETN and INSIG2 in the susceptibility to obesity in african-derived populations from quilombos in Ribeira River Valley.

A fluorose dentária é uma patologia que ocorre durante a formação dos dentes na presença de doses excessivas de fluoreto (F-). Os mecanismos pelos quais o F provoca a fluorose ainda são poucos conhecidos. A influência de fatores genéticos tem sido considerada na suscetibilidade/resistência do indivíduo em desenvolver a fluorose. Duas linhagens de camundongos (A/J e 129P3/J) com diferença na resistência ou suscetibilidade à fluorose dentária foram utilizadas para determinar se a suscetibilidade à fluorose pode ser explicada pela diferença no metabolismo e se há diferença no perfil protéico dos rins e urina destes animais. Para isso, um estudo metabólico foi conduzido com 18 camundongos A/J (suscetível) e 18 129P3 / J (resistente) após o desmame. Cada amostra foi dividida em 3 grupos, com diferentes concentrações de F- na água de beber (0, 10 e 50 ppm F). Uma vez que um estudo piloto revelou que os camundongos A/J ingeriam um maior volume de água quando comparado com o 129P3/J, a concentração de F- na água dada aos camundongos A/J foi ajustada semanalmente a fim de fornecer doses semelhantes de F- para ambas linhagens. Os animais foram mantidos em gaiolas metabólicas (n = 2/gaiola) por 7 semanas, com livre acesso à água e dieta de baixa ingestão de F- (0,95 ppm). A ingestão e excreção de F- foram calculadas, bem como os níveis de F- no plasma, no fêmur e no rim. O grau de fluorose dentária foi avaliado usando análise de fluorescência quantitativa (QLF) e exame clínico. Os perfis proteômicos renal e urinário foram examinados utilizando 2D-PAGE e coloração com azul de Coomassie.. Os dados do estudo metabólico foram testados para diferenças significativas pela ANOVA a 2 critérios (p <0,05). As imagens dos géis e as diferenças estatísticas (ANOVA, p<0,05) foram analisadas pelo programa Image Master Platinum 7.0. Os camundongos da linhagem A/J submetidos à alta concentração de fluoreto apresentaram um grau de fluorose significativamente maior quando comparado com a linhagem 129P3/J. A ingestão total de F- não diferiu significativamente entre as linhagens. A excreção total de F- foi significativamente maior para os camundongos A/J, devido à maior excreção urinária de F-. As duas linhagens não diferiram em relação à absorção F-, mas os animais 129P3/J retiveram significativamente maiores quantidades de F-, que foi consistente com níveis mais elevados de F- no fêmur, no entanto, os níveis de F- no plasma não diferiram significativamente entre as linhagens. Para os rins, a análise quantitativa de intensidade detectou, entre as linhagens A/J e 129P3/J, 122, 126 e 134 spots diferencialmente expressos nos grupos controle, e que receberam baixa e alta concentração de F-, respectivamente. Para a urina, 84 spots diferencialmente expressos foram observados para o grupo controle, 68 para o grupo que recebeu baixa concentração de F- e 66 para o grupo que recebeu alta concentração de F-. Os dados mostraram que há diferenças metabólicas e no perfil de expressão protéica renal e urinária intrínsecas a estas linhagens e que a exposição ao F- é capaz de alterar estes padrões. / Dental fluorosis occurs during tooth formation when excessive doses of fluoride (F) are ingested. The mechanisms that underlie the pathogenesis of dental fluorosis are not known so far. The influence of genetic factors has been considered in individual susceptibility/resistance to develop fluorosis. Two inbred mice strains (A/J and 129P3/J) have been reported to have different susceptibilities to dental fluorosis. They were used in the present study to determine if the susceptibility to dental fluorosis can be explained by alterations in F metabolism and to evaluate if there is difference in the profile of protein expression in kidney and urine of these animals. For this, a metabolic study was conducted with 18 A/J (susceptible) and 18 129P3/J (resistant) weanling mice. Each strain was divided into 3 groups, with differed according to the F concentration given in the drinking water (0, 10 and 50 ppm F). Since a pilot study showed that the A/J mice drank a higher volume of water when compared with the 129P3/J, the F concentration in the water given to the A/J mice was weekly adjusted in order to provide similar F intakes for both strains. The mice were housed in metabolic cages (n=2/cage) for 7 weeks, with free access to water and low-F diet (0.95 ppm). F intake and excretion were calculated, as well as plasma, femur and kidney F levels. The degree of dental fluorosis was assessed using QLF and clinical examination. Renal and urinary proteome profiles were examined using 2D-PAGE and coomassie brilliant blue staining. Data were tested for significant differences by 2-way repeated-measures ANOVA (p<0.05). The gels images and statistical differences (ANOVA, p <0.05) were analyzed by the Image Master Platinum 7.0 software. Significantly higher QLF scores were observed for the A/J mice submitted to 50 ppm F. The total F intake did not significantly differ between the strains. The total F excretion was significantly higher for the A/J mice, due to the higher urinary F excretion. The two strains did not differ in respect to F absorption, but the 129P3/J mice retained significantly higher amounts of F, which was consistent with their higher femur F levels. Plasma F levels, however, did not significantly differ between the strains. For kidney, quantitative intensity analysis detected, between strains A/J and 129P3/J, 122, 126 e 134 spots differentially expressed in the control group, in the group receiving low and high F concentrations, respectively. For urine, 84 spots differentially expressed were detected for control group, 68 for the group receiving low F concentration and 66 for the group receiving high F concentration. Data showed that intrinsic differences occur in the metabolism of F and profile of protein expression between these strains and that these profiles can be altered in the presence of F.

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No. of bitstreams: 2 Dissertação - Denise da Silva Pinheiro.pdf: 1388647 bytes, checksum: e26020f5d13976c2a4920327b71bc5c4 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2013-08-30 / Fundação de Amparo à Pesquisa do Estado de Goiás - FAPEG / In the pathogenesis of type 2 diabetes mellitus (DM2), it is observed that the increased oxidative stress may contribute to decreased insulin production and destruction of pancreatic β cells. Individuals who have no activity of GSTM1 and GSTT1 isoforms may have an increased susceptibility to damage caused by reactive species to pancreatic β cells, since these cells express low levels of antioxidant enzymes. This case-control study aimed to analyze the genotypic profiles of the deletion polymorphism of GSTM1 and GSTT1 genes by molecular assays (conventional PCR and qPCR) to associate these polymorphisms with DM2 risk, considering that studies with this approach have not been conducted in Brazil. Data of clinical, laboratorial and demographic variables of 120 patients and 147 controls were obtained through interviews and information from medical charts (patients) or results of recent clinical and laboratory exams (controls). It was found that diabetic patients had a higher frequency of GSTT1-null genotype (29.2%) than non-diabetic subjects (12.2%), and those with the risk genotype have an increased predisposition to diabetes from approximately 3.2 times (p = 0.0004). However, there was no association of GSTM1-null with DM2 susceptibility. The analysis of the influence of GSTT1 deletion on clinical and biochemical changes in the case group showed that the risk genotype may contribute to the development of DM2 complications related to dyslipidemia, due to the association of GSTT1-null with significantly higher levels of triglycerides (p = 0.0242) and VLDL-cholesterol levels (p = 0.0252) compared to patients without the risk genotype. Additionally, GSTM1-null was associated with elevated levels of fasting glucose, glycated hemoglobin and blood pressure. We emphasized a necessity for applying log-linear analysis in order to explore an interaction between these polymorphisms properly. These results suggest that GSTT1 polymorphism may play an important role in the pathogenesis of DM2 in Brazilian population. Then, this gene could be added to a set of genetic markers to identify individuals at increased risk for developing DM2. Although there was no association of GSTM1 deletion polymorphism with susceptibility to DM2, it was verified the influence of this polymorphism on important clinical parameters related to glycemia and blood pressure levels. This finding suggests that GSTM1-null, GSTT1-null as well, may contribute to the clinical course of diabetic patients. / Na patogênese do diabetes mellitus tipo 2 (DM2), observa-se que o estresse oxidativo aumentado pode contribuir na diminuição da produção de insulina e destruição das células β pancreáticas. Indivíduos que apresentam ausência de atividade das isoformas GSTM1 e GSTT1 podem apresentar uma susceptibilidade aumentada aos danos causados por espécies reativas às células β pancreáticas, uma vez que estas células expressam baixos níveis de enzimas antioxidantes. O presente estudo caso-controle visou analisar os perfis genotípicos do polimorfismo de deleção dos genes GSTM1 e GSTT1 por ensaios moleculares (PCR convencional e qPCR) para associar tais polimorfismos com o risco ao DM2, considerando que ainda não foram realizados estudos com este enfoque no Brasil. Dados clínicolaboratoriais e demográficos de 120 pacientes e 147 controles foram obtidos por meio de entrevistas e consulta a prontuários (pacientes) e a resultados de exames recentes (controles). Foi verificado que os pacientes diabéticos apresentaram uma frequência mais elevada de genótipo GSTT1-nulo (29,2%) do que indivíduos não-diabéticos (12,2%), e que aqueles que apresentam o genótipo de risco possuem uma predisposição aumentada a diabetes de aproximadamente 3,2 vezes (p = 0,0004). No entanto, não houve associação de GSTM1-nulo com a susceptibilidade ao DM2. A análise da influência da deleção de GSTT1 sobre alterações bioquímicas e clínicas no grupo caso demonstrou que o genótipo de risco pode contribuir para o desenvolvimento de complicações do DM2 relacionadas à dislipidemia, em função da associação de GSTT1-nulo com níveis significativamente mais elevados de triglicérides (p = 0,0242) e VLDL-colesterol (p = 0,0252) em comparação aos pacientes sem o genótipo de risco. Adicionalmente, GSTM1-nulo teve associação com níveis elevados de glicemia de jejum, hemoglobina glicada e pressão sanguínea. Foi enfatizada a necessidade de aplicação da análise log-linear para investigar a interação entre os polimorfismos apropriadamente. Os resultados obtidos sugerem que o polimorfismo de deleção de GSTT1 pode desempenhar um importante papel na patogênese do DM2 na população brasileira. Portanto, este gene poderia ser adicionado a um painel de marcadores genéticos para identificação de indivíduos com alto risco ao desenvolvimento do DM2. Embora não tenha ocorrido associação do polimorfismo de deleção de GSTM1 com a susceptibilidade ao DM2, foi verificada a influência deste polimorfismo sobre importantes parâmetros relacionados ao controle glicêmico e pressórico. Estes achados sugerem que GSTM1-nulo, assim como GSTT1-nulo, podem contribuir para a evolução clínica dos pacientes diabéticos.

L’ataxie-télangiectasie (A-T) est une maladie génétique récessive rare de l’enfant, caractérisée par un syndrome neurodégénératif, un déficit immunitaire et des télangiectasies cutanées. La maladie est causée par des mutations bialléliques inactivatrices dans le gène ATM (Ataxia-Telangiectasia Mutated). La maladie implique aussi un risque élevé de développer des cancers, en particulier des leucémies et des lymphomes. Les sujets atteints d’A-T ont également une radiosensibilité accrue. Les femmes de plus de 50 ans apparentées à un enfant atteint d'A-T, porteuses d’une seule copie mutée d’ATM (HetAT), ont un risque plus élevé de cancer du sein que les femmes de la population générale (RR 4,94, 95%CI 1,90 - 12,09). Des études épidémiologiques confirment l’implication d’ATM dans la prédisposition au cancer du sein et montrent que 0,5% à 1% de la population porte une mutation délétère dans ce gène mais le risque de cancer pour les individus HetAT sont encore mal estimés. Dans le premier volet de ma thèse, j’ai recherché des facteurs génétiques constitutionnels pouvant modifier le risque de cancer chez les femmes de la cohorte CoF-AT (cohorte de femmes apparentées à un enfant atteint d’A-T). J’ai ensuite décrit les caractéristiques histologiques et génomiques des tumeurs du sein de sujets HetAT afin d’identifier des biomarqueurs permettant de discriminer les tumeurs ATM des autres tumeurs.Les résultats obtenus dans la première partie de mes travaux menés sur un échantillon de 284 individus HetAT et 174 individus non-HetAT issus de 103 familles A-T montrent que les individus HetAT ont des télomères plus longs que leurs apparentés non-HetAT (p=0.0008). En revanche, la longueur des télomères n’est pas associée au risque de cancer dans cette population. De plus, le SNP rs9257445 (ZNF311) qui est associé à la longueur des télomères chez les individus HetAT n’est pas lui non plus associé au risque de cancer. En revanche les SNPs rs6060627 (BCL2L1) et rs2380205 (ANKRD16) modifient le risque de cancer chez les femmes HetAT et non-HetAT.Les résultats obtenus dans la deuxième partie de la thèse à partir de la description morphologique de 41 tumeurs mammaires montrent que les tumeurs des porteurs d’une mutation dans ATM sont majoritairement de sous-type luminal B. D’un point de vue moléculaire, les 23 tumeurs ATM étudiées ne présentent pas la signature BRCAness associée à de grandes pertes chromosomiques. En revanche, nous avons montré que la majorité des tumeurs ATM sont tétraploïdes et présentent une perte d’hétérozygotie au locus 11q22-23 entrainant une inactivation de l’allèle normal d’ATM dans les tumeurs. De plus, l’analyse du nombre de copies réalisée sur ces tumeurs montre une signature ATM impliquant des pertes des loci 13q14.11-q14.3, 21p11.2-p11.1 et 22q11.23.L’ensemble de ces travaux aura permis de mieux caractériser les caractéristiques génétiques des femmes de la cohorte CoF-AT et de mettre en évidence des bio-marqueurs des tumeurs ATM. / Inherited biallelic mutations in the ATM gene cause Ataxia Telangiectasia (A-T), a multisystemic disorder characterized by neurological, cutaneous and immunological abnormalities. The disease is associated with an elevated risk of malignancies, particularly of lymphoma or leukemia, and a high radiosensitivity. Epidemiological studies have shown that female heterozygote carriers (HetAT) younger than 50 years are at increased risk of breast cancer, as compared to women from the general population (RR 4,94, 95%CI 1,90 - 12,09). Despite the rarity of A-T disease, 0.5 to 1% of the population is estimated to be HetAT. Epidemiological studies have confirmed that some specific truncating or missense variants in ATM are associated with increased breast cancer risk but this risk is not yet well estimated. The first part of my thesis project has consisted in characterizing inherited genetic factors modifying cancer risk in women participating in the prospective cohort CoF-AT (“cohorte de femmes apparentées à un enfant atteint d’A-T). In the second part of my work, I described the morphological and molecular features of ATM breast tumours with the aim to identify biomarkers allowing to distinguished ATM-associated tumours from sporadic tumours.Assessment of the contribution of inherited factors such as SNPs of telomere length on the risk of cancer was performed on 284 HetAT individuals and 174 non-HetAT individuals belonging to 103 A-T families. We showed that HetAT individuals have longer telomeres than their non-HetAT counterparts (p=0.0008). However, we found that telomere length was not associated with cancer risk in our study population. The SNP rs9257445 (ZNF311), which is associated with telomere length in HetAT participants, was not associated with cancer risk. Conversely, SNPs rs6060627 (BCL2L1) and rs2380205 (ANKRD16) modified cancer risk in HetAT and non-HetAT women.Pathology review of 41 ATM-associated breast tumours revealed that these tumours mostly belonged to luminal B molecular subtype. The molecular characterization of 23 ATM-associated tumours did not revealed the BRCAness profile associated with Large-Scale State Transitions. However, we found that ATM tumours were mostly tetraploïd and observed loss of heterozygosity at 11q22-23 in the majority of the tumours and loss of ATM wild type allele. Moreover, copy number losses at loci 13q14.11-q14.3, 21p11.2-p11.1 and 22q11.23 appeared to be specific of ATM tumours.Altogether, this project allowed to better characterize the genetic background of the CoF-AT participants and to highlight biomarkers of ATM breast tumours.

Thesis (PhD (Biomedical Sciences. Molecular Biology and Human Genetics))--University of Stellenbosch, 2009. / Dissertation presented for the degree of Doctor of Philosophy in Medical Biochemistry at Stellenbosch University. / ENGLISH ABSTRACT: The infectious disease tuberculosis (TB) still represents a global threat due to its devastating effect on health and the subsequent high mortality rate. Previous studies have indicated that host genetic factors are implicated in host susceptibility to TB. Since TB is a complex disease, it can be assumed that susceptibility to M. tuberculosis has multiple genetic causative factors (as well as environmental causes). The current study focussed on a number of South African Coloured (SAC) individuals, some of whom were TB cases and others controls. Population substructure was tested in the admixed SAC population as it can be a strong confounding factor for association studies. Our results using the programme STRUCTURE indicated no population substructure in the SAC population. We further investigated the population structure of the SAC group using Affymetrix 500k SNP chip data which showed that the SAC population group has 4 major ancestral components: the Khoesan, European, African and Asian (Indian). A number of candidate polymorphisms in eight genes, previously indicated to play an important role in TB susceptibility, were tested in case-control associations studies. We found statistically significant associations between IFNGR1, IL-8, IL-1Ra and NRAMP1 polymorphisms and TB susceptibility in the SAC population. It has become increasingly evident that gene-gene interactions play a far more important part in an individual’s susceptibility to a complex disease than single polymorphisms would on their own. The importance of epistasis was clearly identifiable in this study with only four associations found between the individual variants and TB susceptibility, but eight instances of statistically significant gene-gene interactions. A combined data set consisting of 106 variants constructed from our database and also used for gene-gene interaction analysis yielded numerous statistically significant interactions. The interaction between the genotype of the human host and the bacterial strain genotype was also investigated and yielded interesting results. Owing to various polymorphisms in several cytokine genes, the protein levels of the main modulators of the immune system, cytokines and chemokines, are changed in several diseases such as infectious diseases and may affect susceptibility or resistance to TB. The functional polymorphisms or haplotype patterns in some of these cytokine genes might be vital for protective immune responses and may serve as biomarkers of protection or susceptibility to TB. The present study investigated 18 cytokines including pro-inflammatory, anti-inflammatory and chemokine factors in healthy (mantoux positive or negative) children using the Linco-plex immunoassay, and investigated potential interactions. The basic research will one day contribute to personalised genetics which may benefit infectious diseases such as TB. If individuals can be identified as potentially more vulnerable, they may require different vaccination strategies, a higher index of suspicion if exposed to TB, and prophylactic treatment. / AFRIKAANSE OPSOMMING: Die infektiewe siekte tuberkulose (TB) is steeds ‘n gevaar wat die hele wêreld bedreig weens die groot impak op gesondheid en die gevolglike hoë mortaliteit. Vorige studies het bevind dat die gasheer se genetiese faktore wel betrokke mag wees by die gasheer se vatbaarheid vir TB. Aangesien TB ‘n komplekse siekte is, kan dit aanvaar word dat vatbaarheid tot M. tuberculosis veelvuldige genetiese oorsaaklike faktore (sowel as omgewingsoorsake) het. Hierdie studie het gefokus op ‘n aantal Suid-Afrikaanse Kleurling (SAC) individue, waarvan sommige TB pasiënte en ander kontroles was. Die gemengde SAC populasie is getoets vir populasie-stratifikasie, aangesien stratifikasie ‘n sterk verwarrende invloed op pasiënt-kontrole studies kan hê. Ons resultate is verkry met behulp van die program STRUCTURE en het aangedui dat daar geen populasie sub-struktuur tussen die pasiënte en kontroles was nie. Ons het ook die populasiesamestelling van die SAC groep ondersoek met data verkrygbaar van die Affymetrix 500k enkel nukleotied polimorfisme mikroskyfie. Hierdie data het getoon dat die SAC populasie uit 4 hoof voorouerlike komponente bestaan naamlik die Khoesan, Europeërs, Afrikane en Asiate (Indiërs). ‘n Aantal kandidaat polimorfismes in agt gene, wat volgens vorige studies ‘n belangrike rol in TB vatbaarheid te speel, was in hierdie pasiënt-kontrole assosiasie studie bestudeer. Ons het statistiese beduidende verwantskappe tussen IFNGR1, IL-8, IL-1Ra en NRAMP1 polimorfismes en TB vatbaarheid in die SAC populasie gevind. Dit het al hoe meer duidelik geword dat geen-geen interaksies ‘n baie belangriker rol in ‘n individu se vatbaarheid vir ‘n komplekse siekte speel as enkel polimorfismes op hul eie. Die belang van epistase kon duidelik in hierdie studie geïdentifiseer word met slegs vier assosiasies wat tussen die individuele variante en TB vatbaarheid gevind is, in vergelyking met agt statisties beduidende geen-geen interaksies. ‘n Gekombineerde datastel wat uit ons databasis saamgestel is en wat 106 variante bevat is ook in ‘n aparte geen-geen interaksie analise gebruik, wat verskeie statisties beduidende interaksies getoon het. Die interaksie tussen die menslike gasheer genotipe en die bakteriese stam genotipe is ook in hierdie studie ondersoek en het interessante resultate opgelewer. Veranderde proteïen uitdrukking van die hoofmoduleerders van die immuunsisteem, sitokine en chemokine, kom voor in verskeie siektes soos infektiewe siektes weens verskillende polimorfismes in verskeie sitokien-gene. Sulke polimorfismes kan ook vatbaarheid vir of weerstandigheid teen TB beïnvloed. Die funksionele polimorfismes of haplotipe patrone in sommige van hierdie sitokien-gene mag noodsaaklik wees vir beskermende immuunresponse en mag ook as biomerkers vir beskerming teen of vatbaarheid vir TB dien. Hierdie studie het 18 sitokiene (insluitend pro-inflammatoriese-, anti-inflammatoriese- en chemokiene faktore), sowel as potensiële interaksies in gesonde (mantoux positiewe of negatiewe) kinders, ondersoek met behulp van die Linco-plex immuno-analise. Hierdie basiese navorsing sal eendag in die toekoms bydrae tot persoonlike genetiese analises wat tot voordeel kan wees vir infektiewe siektes soos TB. Indien individue as potensieël meer vatbaar vir TB geïdentifiseer kan word, kan sulke persone ander vaksineringstrategieë sowel as voorkomende behandeling vereis.

Thesis (MScMedSc)--Stellenbosch University, 2012. / Bibliography / ENGLISH ABSTRACT: The communicable disease tuberculosis (TB) is responsible for millions of deaths each year, on a global scale. At present the contribution of host genetics in TB is generally accepted and, together with environmental aspects (e.g. nutrition and crowding) and the causative bacterium, Mycobacterium tuberculosis (M. tuberculosis); it will possibly have a hand in the outcome of disease. Clearly, TB is a multifaceted disease and the repercussions for studying genetic susceptibility are that many genes will potentially be implicated. To date a variety of genes such as NRAMP1 and HLA have been implicated in influencing the host response to TB, albeit with varying effects in different populations. Some of the more recently implicated genes are the pattern recognition receptors, the Toll-like receptors (TLRs). Genetic variation in theses genes has been associated with a myriad of different diseases, including those of an infectious nature, such as TB. In the case of TB, TLR2 is the most prominent candidate with TLR8 and 9 more recently implicated. One of the more well known genes implicated with TB is the vitamin D receptor (VDR), as the antimicrobial gene cathelicidin (CAMP), one of the most important agents of mycobacterial killing, has a VDR response element in its promoter. TLR2, VDR and CAMP are all connected in a complex pathway essential for the host defence against M. tuberculosis. Nine single nucleotide polymorphisms (SNPs) in three TLR genes (TLR2,8 & 9) were investigated via a case-control approach to determine their potential role in human genetic susceptiblity to TB in the Coloured population of South Africa. The effect of the VDR polymorphism Cdx2 on the expression of cathelicidin mRNA and protein expression was also investigated. Three genes were found to contribute significantly to genetic host susceptibility in the Coloured population of South Africa. An allelic association (p = 0.031) was observed for the TLR8 (located on the X-chromosome) SNP rs3761624, with the A-allele being more prominent in females. Four haplotypes of TLR8 were found to be significantly linked to TB susceptibility with the three SNP haplotype rs3761624-rs3764879-rs3764880, specifically the allelic combination of G/C/A [p = 0.004, OR = 2.67(95% CI: 1.90-3.74)], showing a marked association (p = 0.001). The TLR9 introexon2 boundary SNP rs352139 was significantly associated with TB susceptiblity on a genotypic (P = 0.02) and allelic scale [p = 0.05, OR=0.70; (95% CI: 0.55–0.90)], with the T allele more frequent in controls. The TLR9 two SNP haplotype consisting of rs5743836 and rs352139 was linked (p = 0.037) to TB susceptibility, specifically the combination of the alleles A/T [p = 0.013, OR=0.71; (95% CI: 0.55–0.92)]. No gene-gene interaction between TLR2, TLR8 and TLR9 was observed. No significant conclusions could be drawn from the analysis of the mRNA and protein expression of CAMP in samples harbouring the different genotypes of the VDR polymorphism Cdx2. Genetic variations in the TLR8 and 9 genes were identified as potential factors that influence genetic host susceptibility to tuberculosis in the Coloured population of South Africa. / AFRIKAANSE OPSOMMING: Die oordragbare siekte tuberkulose (TB) is elke jaar verantwoordelik vir miljoene sterftes wêreldwyd. Die invloed van die gasheer genoom op TB vatbaarheid word huidiglik aanvaar, tesame met die invloed van omgewingsfaktore (dieet, oorbevolking ens.) en die bakterium Mycobacterium tuberculosis (M. tuberculosis). Dit is duidelik dat TB ‘n veelvlakkigesiekte is wat beïnvloed sal word deur ‘n menigte verskillende gene. ‘n Verskeidenheid gene is al betrek by TB genetiese vatbaarheid, onder andere NRAMP1 en HLA, hoewel hul effekte in uiteenlopende bevolkings verskil. Sommige van die onlangse gene wat betrek is in TB genetiese vatbaarheid is die Toll-like reseptore (TLRs). Genetiese variasie in hierdie gene is geassosieer met ‘n wye verskeidenheid van siektes, insluitend aansteeklik van aard, onder andere TB. In die geval van TB speel TLR2 ‘n prominente rol, terwyl TLR8 en TLR9 meer onlangs geïmpliseer is. Een van die meer bestudeerde TB vatbaarheidsgene is die vitamiene D reseptor geen (VDR). VDR is direk betrokke in die uitdrukking van die anti-mikrobiale geen cathelicidin (CAMP),’n integrale komponent in die vernietiging van mikobakterieë. Die CAMP geen het ‘n VDR respons-element in sy promotor. Die TLR2, VDR en CAMP gene word verbind deur ‘n komplekse netwerk wat integraal is tot die liggaam se vermoë om TB af te weer. Nege enkel nukleotied polimorfismes (ENPs) in drie gene (TLR2,8 & 9) is vir hierdie studie ondersoek, deur gebruik te maak van ‘n pasiënt-kontrole assosiasiestudies, om te bepaal watter rol hul speel in genetiese vatbaarheid vir TB in die Kleurling bevoling van Suid-Afrika, al dan nie. Die invloed van die VDR polimorfisme Cdx2 op die uitdrukking van die mRNS (boodskapper ribonukleïensuur) en proteïen van die geen CAMP is ook ondersoek. Ons het gevind dat drie gene beduidend bygedra het tot genetiese vatbaarheid vir TB in die Kleurling populasie. ‘n Alleel verwante assosiasie (p = 0.031) was gevind vir die TLR8 SNP rs3761624, waar die A-alleel meer algemeen was in vroue. Vier haplotipes vir TLR8 het beduidende assosiasies met TB vatbaarheid getoon. Die drie SNP haplotipe rs3761624-rs3764879- rs3764880, spesifiek die alleel kombinasie C/G/A [p = 0.004, OR = 2.67(95% CI: 1.90-3.74)] het sterk assosiasie (p = 0.001) met TB getoon. Die TLR9 intron-ekson2 grens SNP, rs352139 het beduidende assosiasie met TB getoon op ‘n genotipiese (p = 0.02) sowel as alleliese skaal [p = 0.05, OR=0.70; (95% CI: 0.55–0.90)], met die T alleel meer algemeen in kontroles. Die twee SNP haplotipe bestaande uit rs5743836 en rs352139 het TB vatbaarheid beïnvloed (p = 0.037), spesifiek die alleliese kombinasie van A/T [p = 0.013, OR=0.71; (95% CI: 0.55–0.92)]. Geen noemenswaardige interaksies tussen TLR2, 8 en 9 is gevind nie. So ook is geen beduidende resultate gevind vir die effek van die VDR SNP Cdx2 op die uitdrukking van CAMP mRNS en proteïen nie. Genetiese variasie in die TLR8 en 9 gene is geïdentifiseer as moontlike faktore wat gasheer genetiese vatbaarheid vir TB in die Kleurlingbevolking van Suid-Afrika beïnvloed. / WW Roome Trust