Mattevi V S, Zembrzuski V M, Hutz M H
Departamento de Ciências Fisiológicas, Fundação Faculdade Federal de Ciências Médicas de Porto Alegre, Porto Alegre, RS, Brasil.
Braz J Med Biol Res. 2007 Jul;40(7):927-32. doi: 10.1590/s0100-879x2006005000114.
The contribution of genetic factors to the development of obesity has been widely recognized, but the identity of the genes involved has not yet been fully clarified. Variation in genes involved in adipocyte differentiation and energy metabolism is expected to have a role in the etiology of obesity. We assessed the potential association of a polymorphism in one candidate gene, peroxisome proliferator-activated receptor-gamma (PPARGgamma), involved in these pathways and obesity-related phenotypes in 335 Brazilians of European descent. All individuals included in the sample were adults. Pregnant women, as well as those individuals with secondary hyperlipidemia due to renal, liver or thyroid disease, and diabetes, were not invited to participate in the study; all other individuals were included. The gene variant PPARG Pro12Ala was studied by a PCR-based method and the association between this genetic polymorphism and obesity-related phenotypes was evaluated by analysis of covariance. Variant allele frequency was PPARG Ala12 = 0.09 which is in the same range as described for European and European-derived populations. No statistically significant differences were observed for mean total cholesterol, LDL cholesterol, HDL cholesterol, or triglyceride levels among PPARG genotypes in either gender. In the male sample, an association between the PPARG Pro12Ala variant and body mass index was detected, with male carriers of the Ala variant presenting a higher mean body mass index than wild-type homozygotes (28.3 vs 26.2 kg/m2, P = 0.037). No effect of this polymorphism was detected in women. This finding suggests that the PPARG gene has a gender-specific effect and contributes to the susceptibility to obesity in this population.
遗传因素对肥胖症发展的作用已得到广泛认可，但其中涉及的基因身份尚未完全明确。参与脂肪细胞分化和能量代谢的基因变异预计在肥胖症的病因中起作用。我们评估了一个候选基因——过氧化物酶体增殖物激活受体γ（PPARGγ）中的一种多态性与335名欧洲裔巴西人肥胖相关表型之间的潜在关联。样本中的所有个体均为成年人。孕妇以及因肾脏、肝脏或甲状腺疾病及糖尿病导致继发性高脂血症的个体未被邀请参与研究；所有其他个体均被纳入。通过基于聚合酶链反应（PCR）的方法研究了PPARG基因Pro12Ala变异，并通过协方差分析评估了这种基因多态性与肥胖相关表型之间的关联。变异等位基因频率为PPARG Ala12 = 0.09，与欧洲及欧洲裔人群的报道范围相同。在任何性别中，PPARG基因各基因型之间的总胆固醇、低密度脂蛋白胆固醇、高密度脂蛋白胆固醇或甘油三酯平均水平均未观察到统计学上的显著差异。在男性样本中，检测到PPARG Pro12Ala变异与体重指数之间存在关联，Ala变异的男性携带者的平均体重指数高于野生型纯合子（28.3对26.2 kg/m²，P = 0.037）。在女性中未检测到这种多态性的影响。这一发现表明PPARG基因具有性别特异性效应，并对该人群的肥胖易感性有影响。
