Loos Ruth J F, Rankinen Tuomo
Human Genomics Laboratory, Pennington Biomedical Research Center, Baton Rouge, LA 70808, USA.
J Am Diet Assoc. 2005 May;105(5 Suppl 1):S29-34. doi: 10.1016/j.jada.2005.02.015.
Obesity is one of the most pressing problems in the industrialized world. The susceptibility to obesity is partly determined by genetic factors, but an "obesity-promoting environment" is typically necessary for its phenotypic expression. Such a genetically mediated susceptibility to environmental exposure is referred to as gene-environment interaction. This article reviews the effect of genotype-diet interactions on body weight and body composition changes. A few well-controlled studies with monozygotic twins have specifically addressed the genetic background of interindividual variation in response to overfeeding or energy restriction. Some individuals will gain or lose weight more easily than others, but subjects sharing the same genotype (monozygotic twins) will respond in a similar way, suggesting that the responsiveness to diet is mediated by their genotype. Further evidence for gene-environment interactions comes from candidate gene studies. Genes involved in pathways regulating energy expenditure and food intake may play a role in the predisposition to obesity. For example, DNA sequence variation in genes encoding the adrenergic receptors and uncoupling proteins are of particular relevance. This growing body of research may help in the development of antiobesity treatments and perhaps genetic tests to predict the risk for obesity.
肥胖是工业化世界中最紧迫的问题之一。肥胖易感性部分由遗传因素决定，但“促肥胖环境”通常是其表型表达所必需的。这种对环境暴露的遗传介导易感性被称为基因-环境相互作用。本文综述了基因型-饮食相互作用对体重和身体成分变化的影响。一些对同卵双胞胎进行的严格对照研究专门探讨了个体对过度喂养或能量限制反应的个体间差异的遗传背景。一些人比其他人更容易增重或减重，但具有相同基因型的受试者（同卵双胞胎）会有相似的反应，这表明对饮食的反应性是由他们的基因型介导的。基因-环境相互作用的进一步证据来自候选基因研究。参与调节能量消耗和食物摄入途径的基因可能在肥胖易感性中起作用。例如，编码肾上腺素能受体和解偶联蛋白的基因中的DNA序列变异尤为相关。这一不断增加的研究成果可能有助于开发抗肥胖治疗方法，或许还能进行基因检测以预测肥胖风险。
