Twin studies of disease concordance are useful to weight the relative contribution of genetic and environmental factors to the cause of common complex disorders. In multiple sclerosis (MS) different twinning rates from geographic areas at different prevalence suggested that heritable and non-heritable factors contribute in different proportions and ways to MS risk in diverse populations. This concept prompted genome-wide association studies, and the implementation of the co-twin control design, that allows stringent experimental approaches in MS-discordant identical pairs, controlling for genetic influences and many other known and unknown factors. The co-twin control design provided important clues on MS molecular model. These studies will be reviewed, focusing on those showing significant differences between affected and healthy co-twins. In some cases, differences that emerged in non-twin patients compared to matched controls were not confirmed in identical MS-discordant pairs, suggesting an 'MS subclinical trait'. Early patterns of magnetic resonance imaging and predictive biomarkers that characterize 'healthy' co-twins may be useful for the identification of a prodromal reversible phase of the disease.

中文翻译：

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解开多发性硬化症的分子机制：孪生研究的贡献。

对疾病一致性的双重研究有助于权衡遗传和环境因素对常见复杂疾病原因的相对贡献。在多发性硬化症（MS）中，不同患病率的地理区域的孪生率不同，表明遗传和非遗传因素在不同人群中对MS风险的贡献比例和方式不同。这个概念促进了全基因组关联研究以及双胞胎对照设计的实施，该研究允许在MS不一致的相同对中采用严格的实验方法，以控制遗传影响以及许多其他已知和未知因素。双胞胎对照设计为MS分子模型提供了重要线索。将对这些研究进行综述，重点是那些显示受影响和健康双胞胎之间存在显着差异的研究。在某些情况下，未配对的非双胞胎患者与配对对照相比，在相同的MS-cordordant对中未确认差异，提示“ MS亚临床特征”。表征“健康”双胞胎的磁共振成像和预测性生物标志物的早期模式可能对识别疾病的前驱性可逆阶段有用。