masterThesis
Estudo da expressão dos genes do metabolismo do ácido fólico e associação com o desenvolvimento de fendas orais
Fecha
2012-08-30Registro en:
SOARES, Clélio Diogo. Estudo da expressão dos genes do metabolismo do ácido fólico e associação com o desenvolvimento de fendas orais. 2012. 90f. Dissertação (Mestrado em Ciências Farmacêuticas) - Centro de Ciências da Saúde, Universidade Federal do Rio Grande do Norte, Natal, 2012.
Autor
Soares, Clélio Diogo
Resumen
Introduction: There is considerable evidence suggesting that folate-related genes play a role in the etiology of oral facial clefts. Clefts are known to have a strong genetic component. The expression profile of genes involved on the pathway and folic acid metabolism which is linked to oral clefts requires appropriate environmental causes in combination with genetic factors that culminate in the failure of fusion of facial processes. Objective: The objective is to perform the association of differential gene expression of folate metabolism genes (MTHFR, MTR, RFC1, MTRR) with the occurrence of oral clefts. Methods: We studied 50 subjects with oral clefts and their mothers, and 50 individuals absent of oral clefts and their mothers, totaling 100 individuals referred cases and 100 controls respectively. For gene expression study, total RNA was extracted from peripheral blood cells, then it was quantified and analyzed for purity by absorbance relation and integrity in MOPS gel. The mRNA samples with good purity and integrity were transcribed to cDNA using reverse transcription kit. The cDNA was used in pre-designed gene expression assays. In a previous study performed by our group were evaluated by PCR-RFLP the MTRR A66G, MTHFR C677T, MTHFR A1298G, MTR A2756G, RFC1 A80G polymorphisms, in this study we evaluated the influence of these polymorphisms on gene expression. It was also performed biochemical, hematological analyzes and a clinical characteristics study of these individuals. We performed statistical analysis considering the significance level of 95% (P <0.050) Results: The consumption of Alcohol was reported as a significant risk factor for the present case mothers (p = 0.001). Regarding the biochemical there were no significant differences between children cases group and their controls which had values of AST, ALT and creatinine within the reference values. The folic acid dosage presented significantly reduced in case mothers group (P = 0.011). In haematological analysis was not observed significant changes in any of the evaluated parameters such as hemoglobin, hematocrit, erythrocyte count, and hematological indices, MCV, MCH and MCHC among the groups. The assessment of gene expression for case mother group showed a significant reduction in mRNA expression in all evaluated genes; for the methionine synthase gene (MTR, p = 0.008), the methionine synthase reductase (MTRR, p = 0.015), the reduced folate carrier 1 (RFC1, P= 0.004) and methylenetetrahydrofolate reductase (MTHFR, P= 0.017) compared with the control group mothers. In the case children group, similar results were obtained, with a significant reduction in mRNA expression of methionine synthase gene (MTR, p = 0.010) and methionine synthase reductase (MTRR, p = 0.034) analysis of genotypes in relation to expression was found that the recessive genotype (CC) for the MTHFR gene A1298C polymorphism is associated with reduced expression of its mRNA. Conclusion: Folate metabolism related genes are low expressed on both case groups of this study, since all four genes (RFC1,MTHFR, MTR, MTR,) were reduced on mothers and two genes (MTR, MTRR) in their children. These down regulated genes represent an increased risk associated with the presence of oral clefts in these individuals.