Navegando por Assunto "Polimorfismo (Genética)"

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Acesso aberto (Open Access)
Análise de componentes principais de variáveis nutricionais e de polimorfismos nos genes MDM2, XRCC1 E MTHFR como fatores de risco para Carcinoma Hepatocelular em pacientes com Hepatite C Crônica
(Universidade Federal do Pará, 2016-03-16) PINHO, Priscila Matos de; DEMACHKI, Samia; http://lattes.cnpq.br/7568391537270652; ARAÚJO, Marília de Souza; http://lattes.cnpq.br/9371703949781020
Introduction: Liver diseases are among the leading causes of morbidity and mortality in the world. Hepatitis C is present in approximately 20% of cases of acute hepatitis and 70% of cases of chronic hepatitis. E has been associated with the presence of accumulation of intrahepatic lipids (fatty liver) and it often progresses to development of liver cirrhosis and hepatocellular carcinoma (HCC) is the leading cause of liver transplantation. Objective: To evaluate the relationship of nutritional variables and polymorphisms of MDM2 gene, MTHFR and XRCC1 with risk to HCC in patients with chronic hepatitis C. Methods: case - control performed with patients with chronic hepatitis C. Cases were patients with chronic HCV infection, those with positive anti-HCV and HCV-RNA for six months or more since the detection of the infection within the clinical presentation parameters. They considered participants in the control group healthy subjects aged> 20 years, of both sexes. They were invited to participate in the voluntary survey. We used a nutritional assessment questionnaire. The presence of MDM2 polymorphisms (rs3730485) was investigated; XRCC1 (rs3213239) and MTHFR (rs1801133). It used the Fisher's exact test, odds ratio, and analysis of Principal Components. Results: For genotyping, it was found similarity in frequency of polymorphisms of MTHFR genes XRCC1 and MDM2 in both groups. The odds ratios that had significant p values were low fruit intake, physical inactivity and BMI> 25 kg / m². The results of principal component analysis are indicative that there are at least three pathophysiologic processes that operate in the cluster of risk factors for HCC, and are strongly related to body fat, alcohol consumption and low consumption of fruits. Conclusion: The patients evaluated aggregate risk factors for the development of HCC.
Acesso aberto (Open Access)
Avaliação de polimorfismos dos genes Timidilato sintase, Metileno-tetrahidrofolato e Metionina sintase em tumores da mama
(Universidade Federal do Pará, 2019-02-25) DURÁN, Miguel Ángel Cáceres; BORGES, Bárbara do Nascimento; http://lattes.cnpq.br/0676220027193876
Breast cancer (BC) is the most common cancer among women in the world and Brazil, after nonmelanoma skin cancer. Polymorphisms in genes involved in the folate pathway have been associated as possible etiological factors of this disease. Thymidylate synthase (TYMS) codes for the thymidylate synthase, responsible for the conversion of deoxyuridine monophosphate (dUMP) to deoxythymidine monophosphate (dTMP). TYMS has a polymorphic tandem repeat in the 5'-UTR region (TSER), which generally contains a triple (3R) or double (2R) repeat of a 28 bp sequence. It is thought that the TSER variants are functionally relevant and are associated with BC risk. Another polymorphism in TYMS is 1494del6 and consists of the variation of a 6 bp sequence (TTAAAG) at position 1494 of the 3'-UTR region. These allelic variants are closely related to the level of expression of the enzyme. Methylenetetrahydrofolate reductase codes for the 5,10- methylenetetrahydrofolate reductase, which regulates the balance between cell methylation and nucleic acid synthesis, providing methyl groups for the conversion of homocysteine to methionine. Within the polymorphisms of MTHFR, the SNPs C677T and A1298C generate a reduced enzymatic activity, affecting the synthesis of nucleic acids and the availability of methyl groups for biochemical processes, which could increase BC risk. Methionine synthase (MTR) codes for the methionine synthase, which catalyzes the remethylation of homocysteine to methionine, an essential amino acid and precursor of S-adenosylmethionine, which is a universal donor of methyl groups involved in methylation reactions, including DNA methylation. The role of this polymorphism in cancer risk is still controversial. The aim of this study was to determine if the polymorphisms of the TYMS, MTHFR and MTR genes increase the BC risk. We worked with 61 samples of patients and 35 controls, it was carried out DNA extraction and purification, PCR amplification of DNA fragments including polymorphisms and their subsequent analysis directly through gel visualization, by PCR-RFLP and/or by automatic sequencing. Genotypic and allelic frequencies were determined and were related to the clinical characteristics of the patients and the molecular type of tumor. An analysis of statistical significance was carried out to evaluate the associations of all the polymorphisms with the risk of developing BC and the clinical characteristics of the patients. It was found that 3R allele of TSER and T and C alleles of C677T and A1298C could be associated to BC, although without statistical significance, and TSER and 1494del6 polymorphisms of TYMS could be related to the risk of developing more aggressive breast tumors, although the association is not statistically significant.
Acesso aberto (Open Access)
Caracterização de polimorfismos nos genes DGAT1 E GH em búfalas (Bubalus bubalis)
(Universidade Federal do Pará, 2014-03-11) SILVA, Caio Santos; MARQUES, José Ribamar Felipe; http://lattes.cnpq.br/0104908318773676
The Buffaloes are domestic animals belonging to Bubalus genus, Bovidae family and Artiodactyla order. Provide meat, milk and workforce. Are quite adapted to the climatic conditions of the state of Pará, producing well in those conditions. However, producers still need tested animals for production characteristics. There were used the technique of SSCP (single-strand conformation polymorphism) and SNP markers (single nucleotideo polymorphism), in order to characterize the 83 buffaloes from murrah and Mediterranean breeds. For the DGAT1, occured allelic frequency of 0.741 for the allele A, 0.253 for the allele B and 0.01 for the allele C. The genotypic frequencies were 0.54 for the AA genotype, 0.39 for the AB genotype, 0.06 for the BB genotype and 0.01 for the AC genotype. For the GH gene was found only one genotype. The DGAT1 gene showed considerable genetic variation and detects the presence of SNPs.
Acesso aberto (Open Access)
Existe uma relação entre as frequências dos polimorfismos do gene TSHR e os marcadores de ancestralidade genética em pacientes com hipotireoidismo congênito primário?
(Universidade Federal do Pará, 2024-10) LOURENÇO, Victor Henrique Botelho; ALVES, Erik Artur Cortinhas; http://lattes.cnpq.br/9125390243566397; HTTPS://ORCID.ORG/0000-0001-8824-8075; SILVA, Luiz Carlos Santana da; http://lattes.cnpq.br/6161491684526382; https://orcid.org/0000-0003-1017-6221
Literature shows a correlation between ethnicities and pathogenic variants of the receptor TSH hormone gene (TSHR). Some of these polymorphisms can be as risk factors for the development of Primary Congenital Hypothyroidism (PCH). In this study, we investigate the relationship between the frequencies of TSHR gene polymorphisms with the genetic influence of African, Amerindian, and European ancestry informative markers in patients diagnosed with PCH in an Amazonian population in Brazil. The study was conducted on samples of 106 patients diagnosed with PCH. Genomic DNA was isolated from peripheral blood samples, and 10 exons from the TSHR were automatically sequenced. Ancestry-Informative Marker identification was performed using a panel of 48 markers, and the results were compared with parental Amerindian, Western European, and Sub-Saharan African populations using Structure v2.3.4 software. Four nucleotide alterations were identified among 49 patients. The distribution of tested ancestry markers among the 106 patients indicated a significant difference in the percentages of Amerindian (32.2%), European (41.80%), and African (25.9%) ancestry. A logistic regression analysis revealed no significant association between the rs2075179 and rs1991517 polymorphisms and genetic ancestry. This study found no evidence of a relationship between polymorphic TSHR gene variants and genetic ancestry markers in patients with PCH.
Acesso aberto (Open Access)
Perfil molecular em genes cyp3a4 e cyp2j2: um caminho para a farmacogenética do Rivaroxaban em uma população do Norte do Brasil
(Universidade Federal do Pará, 2014-01-23) TOSCANO, Paulo Martins; SANTOS, Ney Pereira Carneiro dos; http://lattes.cnpq.br/1290427033107137
In recent years, new anticoagulants have been developed with the purpose of minimizing the difficulties encountered in the clinical management of conventional dru- gs, but there are no published data on its pharmacogenetics. Considering the hypothe- sis that polymorphisms related to its metabolism may be the source of genetic variability, this study aims to make inferences on molecular epidemiology of polymorphisms in CyP3a4 (rs2246709) and CyP2j2 (rs890293) genes related to the metabolism of Rivaroxaban, a new direct factor Xa inhibitor. 136 samples from healthy individuals in a population of northern Brazil with a high degree of inter-ethnic mix, so as to guarantee that the pharmacogenetic goal was achieved, have been subjected to a parallel analysis of genomic ancestry for the individuals investigated. The results sho- wed significant differences among genotypes for CyP3a4 observed in the study com- pared to all ancestral populations for a polymorphism 99,365,719 a> G ( P < 0.05). The mixed population of northern Brazil, therefore, showed differences in the distribution of genotype frequencies in relation to ancestral groups, forming our population. The same finding was not observed for the CyP2j2 gene polymorphism. It is noteworthy that the polymorphism in the CyP3a4 gene in the investigated sample is influenced by indivi- dual ethnic European contribution. Considering the high miscegenation featuring local people, and the advancement of Pharmacogenomics in current medicine, such data can contribute to a better understanding of the pharmacogenetics of that new anticoagulant.
Acesso aberto (Open Access)
Polimorfismo do gene da interleucina IL-1B e sua associação com o risco ao desenvolvimento do câncer gástrico em uma população do norte do Brasil
(Universidade Federal do Pará, 2016-12-22) CASTRO, Yaisa Gomes de; SANTOS, Ândrea Kely Campos Ribeiro dos; http://lattes.cnpq.br/3899534338451625
Cancer is understood as a set of diseases with similar characteristics, but with great heterogeneity that occurs in a random manner and covers both tumor and inflammatory and immune cells. Gastric tumors, in Brazil and notably in the State of Pará, have a high incidence. In general, gastric cancer has a multifactorial etiology. Communication and cellular signaling that regulate the immune system are facilitated by interleukins that represent small, specific proteins, have diverse functions, they regulate transcription factors, role genes, inflammation, differentiation, proliferation, and secretion of antibodies. Single polymorphism nucleotide, in specific IL-1B proinflammatory interleukin gene, is associated with the immune response to H. pylori infection. Thefore variations within the IL-1 family genes were associated with susceptibility to the development of gastric cancer. In this case-control study, we investigated whether the polymorphisms IL-1BF1 (rs16944) and IL-1BE1 (rs1143627) are associated with the risk of developing gastric cancer in a population from the north of Brazil; Compared to their respective genotypes, defined haplotypes and these related to ancestry and their rates. SNPs were genotyped by VIC / FAM (Real Time PCR, Fluorescent, Life Technologies, CA, USA) labeled probes. The biostatistical analyzes showed that for the demographic variables, there were significant differences between the groups in European and African ancestry. The distribution of the genotypic, allelic and haplotype frequencies of the IL-1B gene was not statistically significant between the groups. More comprehensive studies and analyzes are needed to help understand better why these polymorphisms in this population do not appear to be associated with the development of the disease in question.
Acesso aberto (Open Access)
Polimorfismos gênicos do tipo indel: o papel da vulnerabilidade genética no desenvolvimento da neuroinflamação e na fisiopatologia do Transtorno Depressivo Maior
(Universidade Federal do Pará, 2017-07-26) REIS, Deyvson Diego de Lima; BURBANO, Rommel Mario Rodriguéz; http://lattes.cnpq.br/4362051219348099; YAMADA, Elizabeth Sumi; http://lattes.cnpq.br/7240314827308306
The pathophysiology of depression still remains not fully understood. And despite the contributions of the monoaminergic hypothesis to the understanding of neurobiological aspects of this disorder, studies have been carried out to investigate the role of neuroinflammation, polymorphisms in genes that influence inflammatory activity and monoaminergic receptor functions in the development of major depressive disorder (MDD). However, few studies have analyzed the role of upstream inflammatory pathways (such as the role of NFKB1 and PAR1 genes, which are capable of influencing transcription of proinflammatory cytokines) and of the alpha 2 adrenergic receptor encoding gene's polymorphism (ADRA2B gene) in individuals diagnosed with depression. Therefore, the objective of this study was to analyze the role of the INDEL type polymorphisms of NFKB1 (rs28362491), PAR1 (rs11267092) e ADRA2B (rs34667759) genes in the development of major depressive disorder. Twelve patients diagnosed with MDD and 145 healthy controls had blood samples collected and the INDEL polymorphisms of these 3 genes were genotyped by a single multiplex reaction. The multiplex PCR products were separated by capillary electrophoresis and the data analyzed in GeneMapper 3.7 software (Applied Biosystems). This research found a statistically significant association between depression and Del/Del genotype of the ADRA2B gene (p = 0.002): these individuals presented a 6.41 times greater chance of developing depression when compared to Del/Ins and Ins/Ins genotypes. There was no statistical significance between the INDEL polymorphisms of NFKB1 and PAR1 genes and depressive phenotype. Our results suggest that the INDEL marker of the ADRA2B gene (rs34667759), specifically the deletion allele, is a possible genetic biomarker of vulnerability for the development of MDD.