Polimorfismo pro12ala do gene do receptor ativado por proliferadores de peroxissomos gama (Pparg) e fatores de risco para doen?as cardiovasculares em escolares.

Estima-se que um ter?o de todos os ?bitos no mundo ocorra devido ?s doen?as cardiovasculares (DCV). As DCV ocorrem como resultado da intera??o de fatores ambientais e gen?ticos. Alguns fatores de risco modific?veis associados com as doen?as cardiovasculares podem se iniciar j? na inf?ncia, como, obesidade, hipertens?o arterial, dislipidemia, sedentarismo e resist?ncia ? insulina. PPARG (gene do receptor ativado por proliferadores de peroxissomo gama) ? um gene envolvido no metabolismo energ?tico e do tecido adiposo que possui um polimorfismo relativamente comum, o Pro12Ala, cuja freq??ncia varia de 2 a 23% em diferentes grupos ?tnicos, foi originalmente associado com baixo ?ndice de massa corp?rea (IMC) e melhor sensibilidade ? insulina. Com o objetivo de identificar a associa??o entre fatores de risco para DCV e o polimorfismo Pro12Ala PPARG, realizamos estudo transversal com alunos do Ensino Fundamental (7 a 14 anos) de Ouro Preto, MG. Foram avaliados par?metros bioqu?micos (colesterol total e fra??es, triglic?rides, glicose, insulina de jejum, resist?ncia ? insulina), antropom?tricos e nutricionais (IMC, circunfer?ncia de cintura, pregas cut?neas, percentual de gordura corporal) e cl?nicos (press?o arterial) e realizada genotipagem dos indiv?duos por RFLP-PCR. Os dados foram analisados com o programa SPSS15.0. A genotipagem do polimorfismo Pro12Ala foi realizada para 753 crian?as, sendo 52,1% meninas e 47,9% meninos. A frequ?ncia do alelo foi de 5,11%. Foi observada freq??ncia genot?pica de 90,1%; 9,7% e 0,2% para os gen?tipos CC, CG e GG, respectivamente na popula??o geral, cuja distribui??o encontra-se em equil?brio de Hardy-Weinberg. N?o houve diferen?as estat?sticas significativas na distribui??o de alelos e gen?tipos entre meninos e meninas. Foi realizada an?lise de vari?ncia da m?dia para as vari?veis cont?nuas de acordo com o gen?tipo para a popula??o geral e estratificado por sexo. Compara??es entre cada grupo de gen?tipo e fatores de risco para DVC na popula??o total revelou que indiv?duos portadores do alelo polim?rfico G (Ala12) apresentam redu??o significativa nos n?veis de HDL colesterol. Ap?s a estratifica??o por sexo, meninos GG, mas n?o meninas, continuaram apresentando n?veis significativamente menores de HDL colesterol. Estes dados sugerem que meninos carreadores o alelo G podem apresentar risco aumentado de dislipidemia.It is estimated that one third of all deaths worldwide occurs due to cardiovascular diseases (CVD). CVD occur as a result of the interaction of environmental and genetic factors. Some modifiable risk factors associated with cardiovascular disease may begin in childhood, such as obesity, high blood pressure, dyslipidemia, physical inactivity and insulin resistance. PPARG (Peroxisome Proliferator-Activated Receptor Ggamma) is a gene involved in energy metabolism and adipose tissue that has a relatively common polymorphism, the Pro12Ala, whose frequency ranges from 2-23% in different ethnic groups, was originally associated with low body mass index (BMI) and improved insulin sensitivity. Aiming to identify the association of risk factors for CVD and PPARG Pro12Ala polymorphism, we conducted cross-sectional study with elementary school students (7-14 years) of Ouro Preto, Brazil. We evaluated biochemical parameters (total cholesterol, HDL, triglycerides, glucose, fasting insulin, insulin resistance), anthropometric and nutritional (BMI, waist circumference, skinfold thickness, body fat percentage) and clinical (blood pressure) and performed genotyping subjects by PCR-RFLP. Data were analyzed with the program SPSS15.0. Genotyping of Pro12Ala polymorphism was performed for 753 children, 52,1% girls and 47.9% boys. The frequency of allele G was 5.11%. It was observed a genotype frequency of 90,1%; 9,7% and 0,2% for genotypes CC, CG and GG, respectively in the general population, whose distribution is in Hardy-Weinberg equilibrium. There was no statistically significant difference in the distribution of alleles and genotypes between boys and girls. Analysis was performed of the mean variance for continuous variables according to genotype for the general population and stratified for sex. Comparisons between each group of genotype and risk factors for CVD in the overall population showed that individuals carrying the polymorphic allele G (Ala12) showed a significant reduction in HDL cholesterol. After stratification by gender, GG boys but not girls, continued to show significantly lower levels of HDL cholesterol. These data suggest that the G allele children carriers may have increased risk of dyslipidemia