Departamento de Inmunología, Facultad de Medicina, The Madrid Regional Blood Center, University Complutense, Pabellón 5, Planta 4. Avda. Complutense s/n, 28040, Madrid, Spain.
Mol Biol Rep. 2013 Feb;40(2):1767-74. doi: 10.1007/s11033-012-2230-7. Epub 2012 Oct 25.
Obesity is for many scholars the most important starting status that gives rise to Metabolic Syndrome (MS) and Type 2 Diabetes (T2D). In the present paper, a genetically homogeneous Amerindian population, as defined by HLA genes, has been genotyped for one of the MS and T2D predisposing genes: PPAR-γ Ala12 and Pro 12 variants. Ala12 has been negatively associated with obesity, but other authors do not find such an association. Notwithstanding, a meta-analysis that used many subjects clearly demonstrated that PPAR-γ Ala12 bearing ones had a reduced risk for T2D. Our results show that Amerindians do not have association of PPAR-γ2 Ala12 and obesity; the latter was measured by waist circumference values after taken specific Amerindian normal waist parameters. Also, a population genetics study indicates that Pro12 allele was the wild allele, which must have occurred before modern humans left Africa. Ala12 may have appeared in Caucasoids later on, according to our comparisons. Negroids tend to show low or null Ala 12 allele frequencies, while most other populations have a significant frequency, particularly European Caucasoids. This may suggest that appearance of Ala12 allele occurred after populations adapted to an agricultural feeding.
肥胖症是许多学者认为的引发代谢综合征（MS）和 2 型糖尿病（T2D）的最重要起始状态。在本文中，我们对一种具有遗传同质性的美洲印第安人群体进行了基因分型，该人群由 HLA 基因定义，用于研究 MS 和 T2D 易患基因之一：过氧化物酶体增殖物激活受体-γ（PPAR-γ）Ala12 和 Pro12 变异体。Ala12 与肥胖呈负相关，但其他作者并未发现这种关联。然而，一项使用大量受试者的荟萃分析清楚地表明，携带 PPAR-γ Ala12 的人患 T2D 的风险降低。我们的研究结果表明，美洲印第安人没有 PPAR-γ2 Ala12 与肥胖之间的关联；后者是通过采用特定的美洲印第安人正常腰围参数测量的腰围值来确定的。此外，一项群体遗传学研究表明，Pro12 等位基因是野生等位基因，它一定是在现代人类离开非洲之前就已经存在了。根据我们的比较，Ala12 可能是后来在白种人中出现的。黑种人往往显示出较低或零的 Ala12 等位基因频率，而其他大多数人群，尤其是欧洲白种人，具有显著的频率。这可能表明 Ala12 等位基因的出现是在人群适应农业喂养之后发生的。
